UPSTREAM: net: stmmac: dwmac-rk: add rk3228-specific data

UPSTREAM: net: stmmac: dwmac-rk: add rk3228-specific data

Add constants and callback functions for the dwmac on rk3228/rk3229 socs.
As can be seen, the base structure is the same, only registers and the
bits in them moved slightly.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
master commit e7ffd81233334b7755050523cb7e0456ae3d2e53)

Conflicts:

	Documentation/devicetree/bindings/net/rockchip-dwmac.txt
[zx: conflict with rk3366 and rk3399 that have not been sent to upstream.]

Change-Id: Ibae845ded567e11a8428f6f45510cd5443845e17
Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>