ethernet: MediaTek: add ethernet driver for MediaTek ARM-based SoCs

This patch adds ethernet support for Mediatek ARM-based SoCs, including
a minimum setup of the integrated switch.

Cc: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Mark Lee <Mark-MC.Lee@mediatek.com>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
Tested-By: "Frank Wunderlich" <frank-w@public-files.de>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 7044c6a..ff55e03 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -513,4 +513,14 @@
 	  This driver implements support for the (Enhanced) Three-Speed
 	  Ethernet Controller found on Freescale SoCs.
 
+config MEDIATEK_ETH
+	bool "MediaTek Ethernet GMAC Driver"
+	depends on DM_ETH
+	select PHYLIB
+	select DM_GPIO
+	select DM_RESET
+	help
+	  This Driver support MediaTek Ethernet GMAC
+	  Say Y to enable support for the MediaTek Ethernet GMAC.
+
 endif # NETDEVICES