media: zoran: fix some compliance test

Add TODO for "TRY_FMT cannot handle an invalid pixelformat"

We need to set pixelformat in some case.
We should also handle some minimum requirement.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>