[media] v4l2-ioctl: add ctrl_handler to v4l2_fh

This is required to implement control events and is also needed to allow
for per-filehandle control handlers.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
3 files changed