phy: Centralise print about attached phy

Many Ethernet drivers contain the same netdev_info() print statement
about the attached phy. Move it into the phy device code. Additionally
add a varargs function which can be used to append additional
information.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/agere/et131x.c b/drivers/net/ethernet/agere/et131x.c
index 80b706f..825da3af 100644
--- a/drivers/net/ethernet/agere/et131x.c
+++ b/drivers/net/ethernet/agere/et131x.c
@@ -3289,9 +3289,7 @@
 	phydev->autoneg = AUTONEG_ENABLE;
 	adapter->phydev = phydev;
 
-	dev_info(&adapter->pdev->dev,
-		 "attached PHY driver [%s] (mii_bus:phy_addr=%s)\n",
-		 phydev->drv->name, phydev_name(phydev));
+	phy_attached_info(phydev);
 
 	return 0;
 }