[media] m5mols: Fix capture image size register definition

The main capture and the thumbnail image size registers were
erroneously defined to have 1 byte width, resulting in wrong
reported image size. Fix this by changing the registers width
to correct value.

Reported-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: HeungJun, Kim <riverful.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>