Add support for getting and setting framerate via v4l2 controls,
rather than setting a fixed value at module insertion.
Signed-off-by: NJim Paris <jim@jtan.com>
Signed-off-by: NJean-Francois Moine <moinejf@free.fr>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>