[media] pwc: Remove driver specific ioctls

This stems from the v4l1 era, with v4l2 everything can be done with
standardized v4l2 API calls.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>