net: add higmacv300 Ethernet driver for HiSilicon platform

It adds the driver for HIGMACV300 Ethernet controller found on HiSilicon
SoCs like Hi3798CV200.  It's based on a downstream U-Boot driver, but
quite a lot of code gets rewritten and cleaned up to adopt driver model
and PHY API.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
3 files changed