net: phy: Add PHY driver for mv88e61xx switches

The previous mv88e61xx driver was a driver for configuring the
switch, but did not integrate with the PHY/networking system, so
it could not be used as a PHY by U-boot.  This is a complete
rework to support this device as a PHY.

Signed-off-by: Kevin Smith <kevin.smith@elecsyscorp.com>
Acked-by: Prafulla Wadaskar <prafulla@marvell.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Marek Vasut <marex@denx.de>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/include/phy.h b/include/phy.h
index 21459a8..969992c 100644
--- a/include/phy.h
+++ b/include/phy.h
@@ -249,6 +249,7 @@
 int gen10g_shutdown(struct phy_device *phydev);
 int gen10g_discover_mmds(struct phy_device *phydev);
 
+int phy_mv88e61xx_init(void);
 int phy_aquantia_init(void);
 int phy_atheros_init(void);
 int phy_broadcom_init(void);