stmmac: use an unique MDIO bus name.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index ee85a14..96fa2da 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -307,7 +307,7 @@
 	priv->speed = 0;
 	priv->oldduplex = -1;
 
-	snprintf(bus_id, MII_BUS_ID_SIZE, "%x", priv->plat->bus_id);
+	snprintf(bus_id, MII_BUS_ID_SIZE, "stmmac-%x", priv->plat->bus_id);
 	snprintf(phy_id, MII_BUS_ID_SIZE + 3, PHY_ID_FMT, bus_id,
 		 priv->plat->phy_addr);
 	pr_debug("stmmac_init_phy:  trying to attach to %s\n", phy_id);