[media] smiapp: Obtain correct media bus code for try format

The media bus code obtained for try format may have been a code that the
sensor did not even support. Use a supported code with the current pixel
order.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>