[media] marvell-ccic: switch to struct v4l2_fh

Use struct v4l2_fh to represent a filehandle. This fixes the missing
g/s_priority handling of this driver that v4l2-compliance complained
about.

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>