[media] vivid: add support to set CVT, GTF timings

In addition to v4l2_find_dv_timings_cap(), where timings are searched
against the list of preset timings, the incoming timing from v4l2-ctl
is checked against CVT and GTF standards. If it confirms to be CVT or
GTF, it is treated as valid timing and vivid format is updated with
new timings.

Signed-off-by: Prashant Laddha <prladdha@cisco.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>