In addition to the existing 2592x1940 12-bit mode, introduce support
for 2592x1940 10-bit mode.

Following are the register set which control the 10/12 bit mode setting:
MDBIT	0x319d
ADBIT	0x3050
ADBIT1	0x341c
	0x341d

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>