thermal: core: Drop redundant lockdep_assert_held()

Along the lines of commit 24aad192 ("thermal: core: Drop
redundant checks from thermal_bind_cdev_to_trip()") notice that
thermal_unbind_cdev_from_trip() is only called by
thermal_zone_cdev_unbind() under the thermal zone lock, so it
need not use lockdep_assert_held() for that lock.

No functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/3341369.44csPzL39Z@rjwysocki.net

drivers/thermal/thermal_core.c

@@ -891,8 +891,6 @@ static void thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
 {
 	struct thermal_instance *pos, *next;
 
-	lockdep_assert_held(&tz->lock);
-
 	mutex_lock(&cdev->lock);
 	list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 		if (pos->trip == trip && pos->cdev == cdev) {