stepper_enable: Directly call clear_homing_state() on motor off event

Call clear_homing_state() on each motor off event.  This simplifies
the kinematic classes as they no longer need to register and handle
the motor_off event.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/kinematics/hybrid_corexz.py

@@ -42,8 +42,6 @@ class HybridCoreXZKinematics:
         for s in self.get_steppers():
             s.set_trapq(toolhead.get_trapq())
             toolhead.register_step_generator(s.generate_steps)
-        self.printer.register_event_handler("stepper_enable:motor_off",
-                                                    self._motor_off)
         # Setup boundary checks
         max_velocity, max_accel = toolhead.get_max_velocity()
         self.max_z_velocity = config.getfloat(
@@ -97,8 +95,6 @@ class HybridCoreXZKinematics:
                 self.dc_module.home(homing_state)
             else:
                 self.home_axis(homing_state, axis, self.rails[axis])
-    def _motor_off(self, print_time):
-        self.clear_homing_state((0, 1, 2))
     def _check_endstops(self, move):
         end_pos = move.end_pos
         for i in (0, 1, 2):