net: ethernet: sun4i-emac: replace magic number with macro

This patch remove magic numbers in sun4i-emac.c and replace with macros
defined in sun4i-emac.h

Signed-off-by: Conley Lee <conleylee@foxmail.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Link: https://lore.kernel.org/r/tencent_71466C2135CD1780B19D7844BE3F167C940A@qq.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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

The Allwinner A10 has an ethernet controller that seem to be developped
internally by them.

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>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>