phy: mdiobus_register(): initialize all phy_map entries

make sure phy_map entries whose PHY address is masked are initialized
to NULL, given that other code (such as mdiobus_unregister for
instance) assumes that non-NULL phy_map entries are allocated
phy_devices

Signed-off-by: Herbert Valerio Riedel <[e-mail]>
Signed-off-by: Stephen Hemminger <[e-mail]>

drivers/net/phy/mdio_bus.c

···
 	for (i = 0; i < PHY_MAX_ADDR; i++) {
 		struct phy_device *phydev;
 
-		if (bus->phy_mask & (1 << i))
+		if (bus->phy_mask & (1 << i)) {
+			bus->phy_map[i] = NULL;
 			continue;
+		}
 
 		phydev = get_phy_device(bus, i);