Consolidate "Unknown X-Code" to save 16 bytes

Firmware/Marlin_main.cpp

@@ -5810,7 +5810,7 @@ if(eSoundMode!=e_SOUND_MODE_SILENT)
           fCheckModeInit();                       // alternatively invoke printer reset
 		break;
 	default:
-		printf_P(PSTR("Unknown G code: %s\n"), cmdbuffer + bufindr + CMDHDRSIZE);
+		printf_P(MSG_UNKNOWN_CODE, 'G', cmdbuffer + bufindr + CMDHDRSIZE);
     }
 //	printf_P(_N("END G-CODE=%u\n"), gcode_in_progress);
 	gcode_in_progress = 0;
@@ -8936,7 +8936,7 @@ Sigma_Exit:
 	#### End of M-Commands
     */
 	default: 
-		printf_P(PSTR("Unknown M code: %s\n"), cmdbuffer + bufindr + CMDHDRSIZE);
+		printf_P(MSG_UNKNOWN_CODE, 'M', cmdbuffer + bufindr + CMDHDRSIZE);
     }
 //	printf_P(_N("END M-CODE=%u\n"), mcode_in_progress);
 	mcode_in_progress = 0;
@@ -9523,7 +9523,7 @@ Sigma_Exit:
 #endif //DEBUG_DCODES
 
     default:
-        printf_P(PSTR("Unknown D code: %s\n"), cmdbuffer + bufindr + CMDHDRSIZE);
+        printf_P(MSG_UNKNOWN_CODE, 'D', cmdbuffer + bufindr + CMDHDRSIZE);
 	}
   }
 

Firmware/messages.c

@@ -204,3 +204,4 @@ const char MSG_M112_KILL[] PROGMEM_N1 = "M112 called. Emergency Stop."; ////c=20
 const char MSG_ADVANCE_K[] PROGMEM_N1 = "Advance K:"; ////c=13
 const char MSG_POWERPANIC_DETECTED[] PROGMEM_N1 = "POWER PANIC DETECTED"; ////c=20
 const char MSG_LCD_STATUS_CHANGED[] PROGMEM_N1 = "LCD status changed";
+const char MSG_UNKNOWN_CODE[] PROGMEM_N1 = "Unknown %c code: %s\n";

Firmware/messages.h

@@ -204,6 +204,7 @@ extern const char MSG_M112_KILL[];
 extern const char MSG_ADVANCE_K[];
 extern const char MSG_POWERPANIC_DETECTED[];
 extern const char MSG_LCD_STATUS_CHANGED[];
+extern const char MSG_UNKNOWN_CODE[];
 
 #if defined(__cplusplus)
 }