phy: Eliminate references to BUS_ID_SIZE.

Just use the constant 20 to keep things working.

If someone is so motivated, this can be converted over to
dynamic strings.  I tried and it's a lot of work.

But for now this is good enough.
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/phy.h

@@ -79,7 +79,7 @@ typedef enum {
  * Need to be a little smaller than phydev->dev.bus_id to leave room
  * for the ":%02x"
  */
-#define MII_BUS_ID_SIZE	(BUS_ID_SIZE - 3)
+#define MII_BUS_ID_SIZE	(20 - 3)
 
 /*
  * The Bus class for PHYs.  Devices which provide access to
@@ -407,7 +407,7 @@ struct phy_driver {
 /* A Structure for boards to register fixups with the PHY Lib */
 struct phy_fixup {
 	struct list_head list;
-	char bus_id[BUS_ID_SIZE];
+	char bus_id[20];
 	u32 phy_uid;
 	u32 phy_uid_mask;
 	int (*run)(struct phy_device *phydev);