V4L/DVB (8783): v4l: add all missing video_device release callbacks

All drivers that call video_device_register where checked to see if they
set the release callback of struct video_device. Where that callback was
missing it was added.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/c-qcam.c b/drivers/media/video/c-qcam.c
index 2196c1d..17aa0ad 100644
--- a/drivers/media/video/c-qcam.c
+++ b/drivers/media/video/c-qcam.c
@@ -722,6 +722,7 @@
 {
 	.name		= "Colour QuickCam",
 	.fops           = &qcam_fops,
+	.release 	= video_device_release_empty,
 };
 
 /* Initialize the QuickCam driver control structure. */