Upon a S_FMT the input/requested frame size and pixel format is
overwritten by the current sub-device settings.
Fix this so application can actually set the frame size and format.

Fixes: 417d2e50 ("[media] media: platform: add VPFE capture driver support for AM437X")

Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: NBenoit Parrot <bparrot@ti.com>
Acked-by: NLad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>