media: uvcvideo: Refactor uvc_ctrl_set_handle()

media: uvcvideo: Refactor uvc_ctrl_set_handle()

Today uvc_ctrl_set_handle() covers two use-uses: setting the handle and
clearing the handle. The only common code between the two cases is the
lockdep_assert_held.

The code looks cleaner if we split these two usecases in two functions.

We also take this opportunity to use pending_async_ctrls from ctrl where
possible.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20250509-uvc-followup-v1-1-73bcde30d2b5@chromium.org
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>