staging: bcm2835-codec: Ensure all ctrls are set on streamon

Currently the code was only setting some controls from
bcm2835_codec_set_ctrls, but it's simpler to use
v4l2_ctrl_handler_setup to avoid forgetting to adding new
controls to the list.

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