[media] v4l/s5p-mfc: added image size align in VIDIOC_TRY_FMT

Image size for MFC encoder should have size between
8x4 and 1920x1080 with even width and height.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>