netdev: fix drivers/net/phy/ kernel-doc warnings

Fix kernel-doc warnings in drivers/net/phy:

Warning(drivers/net/phy/mdio_bus.c:109): No description found for parameter 'mdio_bus_np'
Warning(drivers/net/phy/mdio_bus.c:109): Excess function parameter 'mdio_np' description in 'of_mdio_find_bus'
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/phy/mdio_bus.c

@@ -96,7 +96,7 @@ static int of_mdio_bus_match(struct device *dev, void *mdio_bus_np)
 }
 /**
  * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
- * @mdio_np: Pointer to the mii_bus.
+ * @mdio_bus_np: Pointer to the mii_bus.
  *
  * Returns a pointer to the mii_bus, or NULL if none found.
  *