Allwinner SoCs have dw hdmi controller v1.32a which exhibits same
magenta line issue as i.MX6Q and i.MX6DL. Enable workaround for it.

Tests show that one iteration is enough.
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180214200906.31509-4-jernej.skrabec@siol.net