Cleanup: remove unused FILAMENT_RUNOUT_SUPPORT define

FILAMENT_RUNOUT_SUPPORT has never been supported in the MK3 branch, and
contains a ton of horrible and unmaintained code that doesn't even
compile anymore.

Since this code is currently polluting a sizable block inside the G0/G1
code block, simply get rid of it.

Firmware/Marlin_main.cpp

@@ -4226,9 +4226,6 @@ void process_commands()
 #endif
 
 	if (!buflen) return; //empty command
-  #ifdef FILAMENT_RUNOUT_SUPPORT
-    SET_INPUT(FR_SENS);
-  #endif
 
 #ifdef CMDBUFFER_DEBUG
   SERIAL_ECHOPGM("Processing a GCODE command: ");
@@ -4680,176 +4677,6 @@ eeprom_update_word((uint16_t*)EEPROM_NOZZLE_DIAMETER_uM,0xFFFF);
     case 0: // G0 -> G1
     case 1: // G1
       if(Stopped == false) {
-
-        #ifdef FILAMENT_RUNOUT_SUPPORT
-            
-            if(READ(FR_SENS)){
-
-                        int feedmultiplyBckp=feedmultiply;
-                        float target[4];
-                        float lastpos[4];
-                        target[X_AXIS]=current_position[X_AXIS];
-                        target[Y_AXIS]=current_position[Y_AXIS];
-                        target[Z_AXIS]=current_position[Z_AXIS];
-                        target[E_AXIS]=current_position[E_AXIS];
-                        lastpos[X_AXIS]=current_position[X_AXIS];
-                        lastpos[Y_AXIS]=current_position[Y_AXIS];
-                        lastpos[Z_AXIS]=current_position[Z_AXIS];
-                        lastpos[E_AXIS]=current_position[E_AXIS];
-                        //retract by E
-                        
-                        target[E_AXIS]+= FILAMENTCHANGE_FIRSTRETRACT ;
-                        
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 400, active_extruder);
-
-
-                        target[Z_AXIS]+= FILAMENTCHANGE_ZADD ;
-
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 300, active_extruder);
-
-                        target[X_AXIS]= FILAMENTCHANGE_XPOS ;
-                        
-                        target[Y_AXIS]= FILAMENTCHANGE_YPOS ;
-                         
-                 
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 70, active_extruder);
-
-                        target[E_AXIS]+= FILAMENTCHANGE_FINALRETRACT ;
-                          
-
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 20, active_extruder);
-
-                        //finish moves
-                        st_synchronize();
-                        //disable extruder steppers so filament can be removed
-                        disable_e0();
-                        disable_e1();
-                        disable_e2();
-                        _delay(100);
-                        
-                        //LCD_ALERTMESSAGEPGM(_T(MSG_FILAMENTCHANGE));
-                        uint8_t cnt=0;
-                        int counterBeep = 0;
-                        lcd_wait_interact();
-                        while(!lcd_clicked()){
-                          cnt++;
-                          manage_heater();
-                          manage_inactivity(true);
-                          //lcd_update(0);
-                          if(cnt==0)
-                          {
-                          #if BEEPER > 0
-                          
-                            if (counterBeep== 500){
-                              counterBeep = 0;
-                              
-                            }
-                          
-                            
-                            SET_OUTPUT(BEEPER);
-                            if (counterBeep== 0){
-if(eSoundMode!=e_SOUND_MODE_SILENT)
-                              WRITE(BEEPER,HIGH);
-                            }
-                            
-                            if (counterBeep== 20){
-                              WRITE(BEEPER,LOW);
-                            }
-                            
-                            
-                            
-                          
-                            counterBeep++;
-                          #else
-                          #endif
-                          }
-                        }
-                        
-                        WRITE(BEEPER,LOW);
-                        
-                        target[E_AXIS]+= FILAMENTCHANGE_FIRSTFEED ;
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 20, active_extruder); 
-                        
-                        
-                        target[E_AXIS]+= FILAMENTCHANGE_FINALFEED ;
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 2, active_extruder); 
-                        
-                 
-                        
-                        
-                        
-                        lcd_change_fil_state = 0;
-                        lcd_loading_filament();
-                        while ((lcd_change_fil_state == 0)||(lcd_change_fil_state != 1)){
-                        
-                          lcd_change_fil_state = 0;
-                          lcd_alright();
-                          switch(lcd_change_fil_state){
-                          
-                             case 2:
-                                     target[E_AXIS]+= FILAMENTCHANGE_FIRSTFEED ;
-                                     plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 20, active_extruder); 
-                        
-                        
-                                     target[E_AXIS]+= FILAMENTCHANGE_FINALFEED ;
-                                     plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 2, active_extruder); 
-                                      
-                                     
-                                     lcd_loading_filament();
-                                     break;
-                             case 3:
-                                     target[E_AXIS]+= FILAMENTCHANGE_FINALFEED ;
-                                     plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 2, active_extruder); 
-                                     lcd_loading_color();
-                                     break;
-                                          
-                             default:
-                                     lcd_change_success();
-                                     break;
-                          }
-                          
-                        }
-                        
-
-                        
-                      target[E_AXIS]+= 5;
-                      plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 2, active_extruder);
-                        
-                      target[E_AXIS]+= FILAMENTCHANGE_FIRSTRETRACT;
-                      plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 400, active_extruder);
-                        
-
-                        //current_position[E_AXIS]=target[E_AXIS]; //the long retract of L is compensated by manual filament feeding
-                        //plan_set_e_position(current_position[E_AXIS]);
-                        plan_buffer_line(target[X_AXIS], target[Y_AXIS], target[Z_AXIS], target[E_AXIS], 70, active_extruder); //should do nothing
-                        plan_buffer_line(lastpos[X_AXIS], lastpos[Y_AXIS], target[Z_AXIS], target[E_AXIS], 70, active_extruder); //move xy back
-                        plan_buffer_line(lastpos[X_AXIS], lastpos[Y_AXIS], lastpos[Z_AXIS], target[E_AXIS], 200, active_extruder); //move z back
-                        
-                        
-                        target[E_AXIS]= target[E_AXIS] - FILAMENTCHANGE_FIRSTRETRACT;
-                        
-                      
-                             
-                        plan_buffer_line(lastpos[X_AXIS], lastpos[Y_AXIS], lastpos[Z_AXIS], target[E_AXIS], 5, active_extruder); //final untretract
-                        
-                        
-                        plan_set_e_position(lastpos[E_AXIS]);
-                        
-                        feedmultiply=feedmultiplyBckp;
-                        
-                     
-                        
-                        char cmd[9];
-
-                        sprintf_P(cmd, PSTR("M220 S%i"), feedmultiplyBckp);
-                        enquecommand(cmd);
-
-            }
-
-
-
-        #endif
-
             get_coordinates(); // For X Y Z E F
 
             // When recovering from a previous print move, restore the originally

Firmware/variants/1_75mm_MK25-RAMBo10a-E3Dv6full.h

@@ -264,13 +264,6 @@
  ADDITIONAL FEATURES SETTINGS
  *------------------------------------*/
 
-// Define Prusa filament runout sensor
-//#define FILAMENT_RUNOUT_SUPPORT
-
-#ifdef FILAMENT_RUNOUT_SUPPORT
-#define FILAMENT_RUNOUT_SENSOR 1
-#endif
-
 // temperature runaway
 #define TEMP_RUNAWAY_BED_HYSTERESIS 5
 #define TEMP_RUNAWAY_BED_TIMEOUT 360

Firmware/variants/1_75mm_MK25-RAMBo13a-E3Dv6full.h

@@ -265,13 +265,6 @@
  ADDITIONAL FEATURES SETTINGS
  *------------------------------------*/
 
-// Define Prusa filament runout sensor
-//#define FILAMENT_RUNOUT_SUPPORT
-
-#ifdef FILAMENT_RUNOUT_SUPPORT
-#define FILAMENT_RUNOUT_SENSOR 1
-#endif
-
 // temperature runaway
 #define TEMP_RUNAWAY_BED_HYSTERESIS 5
 #define TEMP_RUNAWAY_BED_TIMEOUT 360

Firmware/variants/1_75mm_MK25S-RAMBo10a-E3Dv6full.h

@@ -264,13 +264,6 @@
  ADDITIONAL FEATURES SETTINGS
  *------------------------------------*/
 
-// Define Prusa filament runout sensor
-//#define FILAMENT_RUNOUT_SUPPORT
-
-#ifdef FILAMENT_RUNOUT_SUPPORT
-#define FILAMENT_RUNOUT_SENSOR 1
-#endif
-
 // temperature runaway
 #define TEMP_RUNAWAY_BED_HYSTERESIS 5
 #define TEMP_RUNAWAY_BED_TIMEOUT 360

Firmware/variants/1_75mm_MK25S-RAMBo13a-E3Dv6full.h

@@ -265,13 +265,6 @@
  ADDITIONAL FEATURES SETTINGS
  *------------------------------------*/
 
-// Define Prusa filament runout sensor
-//#define FILAMENT_RUNOUT_SUPPORT
-
-#ifdef FILAMENT_RUNOUT_SUPPORT
-#define FILAMENT_RUNOUT_SENSOR 1
-#endif
-
 // temperature runaway
 #define TEMP_RUNAWAY_BED_HYSTERESIS 5
 #define TEMP_RUNAWAY_BED_TIMEOUT 360

Firmware/variants/1_75mm_MK3-EINSy10a-E3Dv6full.h

@@ -401,13 +401,6 @@
  ADDITIONAL FEATURES SETTINGS
  *------------------------------------*/
 
-// Define Prusa filament runout sensor
-//#define FILAMENT_RUNOUT_SUPPORT
-
-#ifdef FILAMENT_RUNOUT_SUPPORT
-#define FILAMENT_RUNOUT_SENSOR 1
-#endif
-
 // temperature runaway
 #define TEMP_RUNAWAY_BED_HYSTERESIS 5
 #define TEMP_RUNAWAY_BED_TIMEOUT 360

Firmware/variants/1_75mm_MK3S-EINSy10a-E3Dv6full.h

@@ -405,13 +405,6 @@
  ADDITIONAL FEATURES SETTINGS
  *------------------------------------*/
 
-// Define Prusa filament runout sensor
-//#define FILAMENT_RUNOUT_SUPPORT
-
-#ifdef FILAMENT_RUNOUT_SUPPORT
-#define FILAMENT_RUNOUT_SENSOR 1
-#endif
-
 // temperature runaway
 #define TEMP_RUNAWAY_BED_HYSTERESIS 5
 #define TEMP_RUNAWAY_BED_TIMEOUT 360