net: add hifemac Ethernet driver for HiSilicon platform

It adds the driver for HIFEMAC Ethernet controller found on HiSilicon
SoCs like Hi3798MV200.  It's based on the mainstream linux driver, but
quite a lot of code gets rewritten and cleaned up to adopt u-boot driver
model.

Signed-off-by: Yang Xiwen <forbidden405@outlook.com>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 29304fd..62c4763 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -903,6 +903,15 @@
 	  This Driver support MediaTek Ethernet GMAC
 	  Say Y to enable support for the MediaTek Ethernet GMAC.
 
+config HIFEMAC_ETH
+	bool "HiSilicon Fast Ethernet Controller"
+	select DM_CLK
+	select DM_RESET
+	select PHYLIB
+	help
+	  This driver supports HIFEMAC Ethernet controller found on
+	  HiSilicon SoCs.
+
 config HIGMACV300_ETH
 	bool "HiSilicon Gigabit Ethernet Controller"
 	select DM_RESET