Some sensors (like the one in Nokia N900) provide metadata in the first
couple of lines. Make that information information available to the
pipeline.

Use u16 instead, this is a 16-bit value.
Signed-off-by: NIvaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>