media: common: Add v4l2_find_nearest_size_conditional()

v4l2_find_nearest_size() returns a mode from sensor driver's mode list
that is a best match width and height wise for the sensor. Some drivers
have different set of available modes depending on the number of lanes.
While this could be handled within a driver by providing different lists
of modes, provide a helper v4l2_find_nearest_size_conditional() to ignore
modes that aren't available.

Also use size_t for the array index and remove extra commas while at it.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>