Add DT support. Use it to get the reset and pwdn pins (if there are any).
Tested with one sensor requiring reset/pwdn and one sensor that doesn't
have reset/pwdn pins.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>