All platforms are now using the digital gain from the AgcStatus, so the AgcPrepareStatus and prepare() methods can be tidied up. Signed-off-by: David Plowman <david.plowman@raspberrypi.com> Signed-off-by: Naushir Patuck <naush@raspberrypi.com> Reviewed-by: Naushir Patuck <naush@raspberrypi.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>