net: mscc: ocelot: remove duplicate ocelot_port_dev_check

A helper for checking whether a net_device belongs to mscc_ocelot
already existed and did not need to be rewritten. Use it.

Fixes: 319e4dd1 ("net: mscc: ocelot: introduce conversion helpers between port and netdev")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20201011092041.3535101-1-vladimir.oltean@nxp.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mscc/ocelot_net.c

@@ -669,7 +669,8 @@ struct net_device *ocelot_port_to_netdev(struct ocelot *ocelot, int port)
 	return priv->dev;
 }
 
-static bool ocelot_port_dev_check(const struct net_device *dev)
+/* Checks if the net_device instance given to us originates from our driver */
+static bool ocelot_netdevice_dev_check(const struct net_device *dev)
 {
 	return dev->netdev_ops == &ocelot_port_netdev_ops;
 }
@@ -678,7 +679,7 @@ int ocelot_netdev_to_port(struct net_device *dev)
 {
 	struct ocelot_port_private *priv;
 
-	if (!dev || !ocelot_port_dev_check(dev))
+	if (!dev || !ocelot_netdevice_dev_check(dev))
 		return -EINVAL;
 
 	priv = netdev_priv(dev);
@@ -907,12 +908,6 @@ static int ocelot_port_obj_del(struct net_device *dev,
 	return ret;
 }
 
-/* Checks if the net_device instance given to us originate from our driver. */
-static bool ocelot_netdevice_dev_check(const struct net_device *dev)
-{
-	return dev->netdev_ops == &ocelot_port_netdev_ops;
-}
-
 static int ocelot_netdevice_port_event(struct net_device *dev,
 				       unsigned long event,
 				       struct netdev_notifier_changeupper_info *info)