sunxi: Add sun5i support

sunxi: Add sun5i support

Add support for the Allwinner A13 and A10s SoCs also know as the Allwinner
sun5i family, and the A13-OLinuXinoM A13 based and r7-tv-dongle A10s based
boards.

The only differences compared to the already supported sun4i and sun7i
families are all in the DRAM controller initialization:

-Different hcpr values
-Different MBUS settings
-Some other small initialization changes

Signed-off-by: Henrik Nordstrom <henrik@henriknordstrom.net>
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>