arm64: dts: allwinner: sun50i-h6-pine-h64: state that the DT supports the modelA

The current sun50i-h6-pine-h64 DT does not specify which model (A or B)
it supports.
When this file was created, only modelA was existing, but now both model
exists and with the time, this DT drifted to support the model B since it is
the most common one.
Furtheremore, some part of the model A does not work with it like ethernet and
HDMI connector (as confirmed by Jernej on IRC).

So it is time to settle the issue, and the easiest way was to state that
this DT is for model B.
Easiest since only a small name changes is required.
Doing the opposite (stating this file is for model A) will add changes (for
ethernet and HDMI) and so, will break too many setup.

But as asked by the maintainer this patch state this file is for model A.
In the process this patch adds the missing compoments to made it work on
model A.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>