This is only needed for drivers that do not use vb2_fop_release().
Note that vb2_queue_release() is *not* the counterpart of vb2_queue_init()
as some drivers here seem to think.

Also use vb2_video_unregister_device() to automatically stop streaming
at unregister time for those drivers that set vdev->queue.

Note that sun4i-csi didn't unregister the video device at all. That's
now fixed.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>