Fix compiler warning: sketch/stepper.cpp:1499:6: warning: unused parameter 'address' [-Wunused-parameter].

Firmware/stepper.cpp

@@ -1496,16 +1496,16 @@ void babystep(const uint8_t axis,const bool direction)
 }
 #endif //BABYSTEPPING
 
+#if defined(DIGIPOTSS_PIN) && DIGIPOTSS_PIN > -1
 void digitalPotWrite(int address, int value) // From Arduino DigitalPotControl example
 {
-  #if defined(DIGIPOTSS_PIN) && DIGIPOTSS_PIN > -1
     digitalWrite(DIGIPOTSS_PIN,LOW); // take the SS pin low to select the chip
     SPI.transfer(address); //  send in the address and value via SPI:
     SPI.transfer(value);
     digitalWrite(DIGIPOTSS_PIN,HIGH); // take the SS pin high to de-select the chip:
     //delay(10);
-  #endif
 }
+#endif
 
 void EEPROM_read_st(int pos, uint8_t* value, uint8_t size)
 {

Firmware/stepper.h

@@ -92,8 +92,9 @@ extern bool y_min_endstop;
 extern bool y_max_endstop;
 
 void quickStop();
-
+#if defined(DIGIPOTSS_PIN) && DIGIPOTSS_PIN > -1
 void digitalPotWrite(int address, int value);
+#endif //defined(DIGIPOTSS_PIN) && DIGIPOTSS_PIN > -1
 void microstep_ms(uint8_t driver, int8_t ms1, int8_t ms2);
 void microstep_mode(uint8_t driver, uint8_t stepping);
 void st_current_init();