The ISC driver currently supports ITU-R 601 encoding which
utilizes the external hsync and vsync signals. ITU-R 656
format removes the need for these pins by embedding the
sync pulses within the data packet.

To support this feature, enable necessary register bits
when this feature is enabled via device tree.
Signed-off-by: Ken Sloat <ksloat@aampglobal.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>