Splits out the dither register bits and introduces
the same config enumerations as in the rockchip kernel tree.
Tested to fix the banding on my ASUS C201.
Signed-off-by: Urja Rannikko <urjaman@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20190318154412.26994-1-urjaman@gmail.com