netdev/phy: Make get_phy_id() static and quit EXPORTing it.

This function is only referenced from within phy_device.c, so there is
no reason to export it.  In fact, we can make it static.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/phy_device.c

@@ -207,7 +207,7 @@ static struct phy_device* phy_device_create(struct mii_bus *bus,
  * Description: Reads the ID registers of the PHY at @addr on the
  *   @bus, stores it in @phy_id and returns zero on success.
  */
-int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id)
+static int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id)
 {
 	int phy_reg;
 
@@ -230,7 +230,6 @@ int get_phy_id(struct mii_bus *bus, int addr, u32 *phy_id)
 
 	return 0;
 }
-EXPORT_SYMBOL(get_phy_id);
 
 /**
  * get_phy_device - reads the specified PHY device and returns its @phy_device struct