FROMLIST: net: ethernet: arc: Keep emac compatibility for more Rockchip SoCs

On the RK3066/RK3188, there was fixed GRF offset configuration to set emac
and fixed DIV2 mac TX/RX clock. So, we need to easily set and fit to other
SoCs (RK3036) which maybe have different GRF offset, and need adjust mac
TX/RX clock.

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

Bug: 25923642
Patchset: support emac driver patch[2/3].

(am from https://patchwork.kernel.org/patch/7981641/)
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Change-Id: I999e19ab4e9c9219d2f98295ccb50711c308f812
1 file changed