fix STM32 compile problem

Author: Richard Unger

src/communication/StepDirListener.h

@@ -4,6 +4,12 @@
 #include "Arduino.h"
 #include "../common/foc_utils.h"
 
+
+#if defined(_STM32_DEF_)
+#define PinStatus int
+#endif
+
+
 /**
  * Step/Dir listenner class for easier interraction with this communication interface.
  */
@@ -47,7 +53,7 @@ class StepDirListener
     int pin_step; //!< step pin
     int pin_dir; //!< direction pin
     long count; //!< current counter value - should be set to 0 for homing
-    int polarity = RISING; //!< polarity of the step pin
+    PinStatus polarity = RISING; //!< polarity of the step pin
 
   private:
     float* attached_variable = nullptr; //!< pointer to the attached variable