net: phy: stop exporting phy_driver_unregister

After 42e2a9e11a1d ("net: phy: dp83640: improve phydev and driver
removal handling") we can stop exporting also phy_driver_unregister().

Signed-off-by: Heiner Kallweit <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Paolo Abeni <[e-mail]>

drivers/net/phy/phy_device.c

···
 	return 0;
 }
 
+static void phy_driver_unregister(struct phy_driver *drv)
+{
+	driver_unregister(&drv->mdiodrv.driver);
+}
+
 int phy_drivers_register(struct phy_driver *new_driver, int n,
 			 struct module *owner)
 {
···
 	return ret;
 }
 EXPORT_SYMBOL(phy_drivers_register);
-
-void phy_driver_unregister(struct phy_driver *drv)
-{
-	driver_unregister(&drv->mdiodrv.driver);
-}
-EXPORT_SYMBOL(phy_driver_unregister);
 
 void phy_drivers_unregister(struct phy_driver *drv, int n)
 {

include/linux/phy.h

···
 		return genphy_read_status(phydev);
 }
 
-void phy_driver_unregister(struct phy_driver *drv);
 void phy_drivers_unregister(struct phy_driver *drv, int n);
 int phy_drivers_register(struct phy_driver *new_driver, int n,
 			 struct module *owner);