[media] omap3isp: ccdc: Disable the video port when unused

The video port doesn't support YUV formats. Disable it when the CCDC
sink pad format is set to YUV instead of leaving it enabled and relying
on downstream modules not to process data they receive from the video
port.

Experiments showed that this fixes some of the CCDC failures to stop,
especially in BT.656 mode.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Enrico Butera <ebutera@users.sourceforge.net>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>