Utilise the new FixedPoint type to explicitly calculate gains for AWB in Q4.8 format. This ensures that reporting of gains in metadata reflect the true AWB gains applied. Reviewed-by: Isaac Scott <isaac.scott@ideasonboard.com> Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>