vc04_services: bcm2835-codec: Set port format from s_selection

s_selection allows the crop region of an uncompressed pixel
format to be specified, but it wasn't passing the setting on to
the firmware. Depending on call order this would potentially
mean that the crop wasn't actioned.

Set the port format on s_selection if we have a component created.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>