phy: Change mii_bus id field to a string

Having the id field be an int was making more complex bus topologies
excessively difficult.  For now, just convert it to a string, and
change all instances of "bus->id = val" to
snprintf(id, MII_BUS_ID_LEN, "%x", val).

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/fec_mpc52xx.c b/drivers/net/fec_mpc52xx.c
index 58b71e6..43b5f30 100644
--- a/drivers/net/fec_mpc52xx.c
+++ b/drivers/net/fec_mpc52xx.c
@@ -198,7 +198,7 @@
 	struct phy_device *phydev;
 	char phy_id[BUS_ID_SIZE];
 
-	snprintf(phy_id, BUS_ID_SIZE, PHY_ID_FMT,
+	snprintf(phy_id, BUS_ID_SIZE, "%x:%02x",
 			(unsigned int)dev->base_addr, priv->phy_addr);
 
 	priv->link = PHY_DOWN;