sunxi: Use PG3 - PG8 as io-pins for mmc1

sunxi: Use PG3 - PG8 as io-pins for mmc1

None of the known sunxi devices actually use mmc1 routed through PH, where
as some devices do actually use mmc1 routed through PG, so change the routing
of mmc1 to PG. If in the future we encounter devices with mmc1 routed through
PH, we will need to change things to be a bit more flexible.

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