media: venus: keep resolution when adjusting format

When checking a format for validity, the resolution is reset to 1280x720
whenever the pixel format is not supported. This behavior can mislead
user-space into believing that this is the only resolution supported,
and looks strange considering that if we try/set the same format with
just the pixel format changed to a valid one, the call will this time
succeed without altering the resolution.

Resolution is managed independently of the pixel format, so remove this
reset.

Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Acked-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>