Apply const to tmc_sensorless_homing

Marlin/src/feature/tmc_util.cpp

@@ -581,7 +581,7 @@ void _tmc_say_sgt(const TMC_AxisEnum axis, const int8_t sgt) {
 
 #if ENABLED(SENSORLESS_HOMING)
 
-  void tmc_sensorless_homing(TMC2130Stepper &st, bool enable/*=true*/) {
+  void tmc_sensorless_homing(TMC2130Stepper &st, const bool enable/*=true*/) {
     #if ENABLED(STEALTHCHOP)
       st.coolstep_min_speed(enable ? 1024UL * 1024UL - 1UL : 0);
       st.stealthChop(!enable);

Marlin/src/feature/tmc_util.h

@@ -97,7 +97,7 @@ void monitor_tmc_driver();
  * Defined here because of limitations with templates and headers.
  */
 #if ENABLED(SENSORLESS_HOMING)
-  void tmc_sensorless_homing(TMC2130Stepper &st, bool enable=true);
+  void tmc_sensorless_homing(TMC2130Stepper &st, const bool enable=true);
 #endif
 
 #if ENABLED(HAVE_TMC2130)