[media] marvell-ccic: implement control events

Now that this driver uses v4l2_fh, it is trivial to add support for
control events. Again, this fixes a v4l2-compliance failure.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>