Enable M401 and M402 for deltas with allen key z-probes.

Marlin/Marlin_main.cpp

  */
 inline void gcode_M400() { st_synchronize(); }
 
-#if defined(ENABLE_AUTO_BED_LEVELING) && defined(SERVO_ENDSTOPS) && not defined(Z_PROBE_SLED)
+#if defined(ENABLE_AUTO_BED_LEVELING) && (defined(SERVO_ENDSTOPS) || defined(Z_PROBE_ALLEN_KEY)) && not defined(Z_PROBE_SLED)
 
   /**
    * M401: Engage Z Servo endstop if available
         gcode_M400();
         break;
 
-      #if defined(ENABLE_AUTO_BED_LEVELING) && defined(SERVO_ENDSTOPS) && not defined(Z_PROBE_SLED)
+      #if defined(ENABLE_AUTO_BED_LEVELING) && (defined(SERVO_ENDSTOPS) || defined(Z_PROBE_ALLEN_KEY)) && not defined(Z_PROBE_SLED)
         case 401:
           gcode_M401();
           break;