sunxi: video: Enable video on sun8i, which supports LCD but not HDMI

The A23 (sun8i) only has lcd output support, so allow building the video code
without HDMI support for use with the A23.

Also the A23 has the same reset bits (and necessity to enable the DRC block)
as the sun6i, so enable those bits for sun8i too.

Note building without HDMI support is useful for the A13 (sun5i variant) too,
as that one does not have HDMI either.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>