Added Z_PROBE_PIN to #define for Z_PROBE_AND_ENDSTOP support.

Marlin/pins_RAMPS_13.h

@@ -64,7 +64,7 @@
 
 #if defined(Z_PROBE_ANDENDSTOP)
   // Define a pin to use as the signal pin on Arduino for the Z_PROBE endstop.
- #define 32
+ #define Z_PROBE_PIN 32
 #endif
 
 #if defined(FILAMENT_RUNOUT_SENSOR)