[media] adv7180: Add cropcap operation

Add support to get the pixel aspect ratio depending on the current
standard (50 vs 60 Hz).

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>