phy: Add an mdio_device structure

Not all devices attached to an MDIO bus are phys. So add an
mdio_device structure to represent the generic parts of an mdio
device, and place this structure into the phy_device.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/phy/microchip.c b/drivers/net/phy/microchip.c
index 99df5bc..5e34b49 100644
--- a/drivers/net/phy/microchip.c
+++ b/drivers/net/phy/microchip.c
@@ -68,7 +68,7 @@
 
 static int lan88xx_probe(struct phy_device *phydev)
 {
-	struct device *dev = &phydev->dev;
+	struct device *dev = &phydev->mdio.dev;
 	struct lan88xx_priv *priv;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -89,7 +89,7 @@
 
 static void lan88xx_remove(struct phy_device *phydev)
 {
-	struct device *dev = &phydev->dev;
+	struct device *dev = &phydev->mdio.dev;
 	struct lan88xx_priv *priv = phydev->priv;
 
 	if (priv)