Corrected retract() call for use of auto probe without sled enabled.

Marlin/Marlin_main.cpp

       }
     #endif
 #if defined (ENABLE_AUTO_BED_LEVELING) && (PROBE_SERVO_DEACTIVATION_DELAY > 0)
-//    if (axis==Z_AXIS) retract_z_probe();
-#endif
+  #ifndef Z_PROBE_SLED
+    if (axis==Z_AXIS) retract_z_probe();
+  #endif#
+endif
 
   }
 }