drm/sun4i: Move and expand DW HDMI PHY register macros

DW HDMI PHY macros are moved to header file and expanded with the
registers present on newer SoCs like H3 and H5.

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/20180301213442.16677-12-jernej.skrabec@siol.net