sunxi: dts: sun8i: Add Allwinner A83T dtsi

Allwinner A83T is new octa-core cortex-a7 SOC.
This adds the basic dtsi, the clocks differs from
earlier sun8i SOCs.

This is not yet included in kernel.

Signed-off-by: Vishnu Patekar <vishnupatekar0510@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>