media: atmel: atmel-isc: add checks for limiting frame sizes

When calling the subdev, certain subdev drivers will overwrite the
frame size and adding sizes which are beyond the ISC's capabilities.
Thus we need to ensure the frame size is cropped to the maximum caps.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>