net: Add davicom wemac ethernet driver found on Allwinner A10 SoC's

The Allwinner A10 has an ethernet controller that is advertised as
coming from Davicom.

The exact feature set of this controller is unknown, since there is no
public documentation for this IP, and this driver is mostly the one
published by Allwinner that has been heavily cleaned up.

Signed-off-by: Stefan Roese <sr@denx.de>
ARM: sunxi: Add wemac to sun4i dtsi

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
ARM: sun4i: Add muxing options for the ethernet controller

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
ARM: cubieboard: Enable ethernet (WEMAC) support in dts

Signed-off-by: Stefan Roese <sr@denx.de>
ARM: hackberry: dt: Add Ethernet controller to the Hackberry device tree

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Run checkpatch on it. need to test it