Delay after homing_backoff for CoreXY sensorless homing (#17273)

Marlin/src/module/motion.cpp

         #endif
         homing_feedrate(axis)
       );
+
+      #if ENABLED(SENSORLESS_HOMING)
+        planner.synchronize();
+        #if IS_CORE
+          if (axis != NORMAL_AXIS) safe_delay(200);  // Short delay to allow belts to spring back
+        #endif
+      #endif
     }
   #endif