sunxi: Sync dts files with the linux kernel

Copy over all the latest dts changes from mripard/sunxi/dt-for-4.2 ,
this gives us a proper dtsi file for the A33 rather then abusing
sun8i-a23.dtsi for this.

And this replaces our minimal (dummy) sun7i-a20-mk808c and
sun8i-a33-astar-mid756 dts files with proper ones.

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