Add option to only check endstop when homing

Marlin/stepper.h

@@ -44,6 +44,8 @@ void st_wake_up();
 void checkHitEndstops(); //call from somwhere to create an serial error message with the locations the endstops where hit, in case they were triggered
 void endstops_hit_on_purpose(); //avoid creation of the message, i.e. after homeing and before a routine call of checkHitEndstops();
 
+void enable_endstops(bool check); // Enable/disable endstop checking
+
 void checkStepperErrors(); //Print errors detected by the stepper
 
 void finishAndDisableSteppers();