V4L/DVB (12084): ov511: mark as deprecated

Mark the v4l1 ov511 as deprecated as we now have ov511 support in
the gspca ov519 driver. Note we should really also keep track of this
in Documentation/feature-removal-schedule.txt, but that is not
part of the v4l-dvb tree.

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