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/pasemi_mac.c b/drivers/net/pasemi_mac.c
index 2e39e028..bcd7f98 100644
--- a/drivers/net/pasemi_mac.c
+++ b/drivers/net/pasemi_mac.c
@@ -1012,7 +1012,7 @@
 		goto err;
 
 	phy_id = *prop;
-	snprintf(mac->phy_id, BUS_ID_SIZE, PHY_ID_FMT, (int)r.start, phy_id);
+	snprintf(mac->phy_id, BUS_ID_SIZE, "%x:%02x", (int)r.start, phy_id);
 
 	of_node_put(phy_dn);