[media] adv7604: restart STDI once if format is not found

The STDI block may measure wrong values, especially for lcvs and lcf. If the
driver can not find any valid timing, the STDI block is restarted to measure
the video timings again. The function will return an error, but the restart of
STDI will generate a new STDI interrupt and the format detection process will
restart.

Signed-off-by: Mats Randgaard <matrandg@cisco.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>