LSC gradient parameters are currently computed during prepare() phase. Because these parameters can be computed only one time and stay constant for each frame after, move the computation to the configure() function. Signed-off-by: Florian Sylvestre <fsylvestre@baylibre.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>