net: phy: add phy_modify() accessor

Add phy_modify() convenience accessor to complement the mdiobus
counterpart.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/phy.h b/include/linux/phy.h
index af1a740..135aba5 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -762,6 +762,7 @@ static inline int __phy_write(struct phy_device *phydev, u32 regnum, u16 val)
 }
 
 int __phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set);
+int phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set);
 
 /**
  * phy_interrupt_is_valid - Convenience function for testing a given PHY irq