ionic: cleanly release devlink instance

The failure to register devlink will leave the system with dangled
devlink resource, which is not cleaned if devlink_port_register() fails.

In order to remove access to ".registered" field of struct devlink_port,
require both devlink_register and devlink_port_register to success and
check it through device pointer.

Fixes: fbfb803 ("ionic: Add hardware init and device commands")
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/pensando/ionic/ionic_devlink.c

@@ -91,20 +91,20 @@ int ionic_devlink_register(struct ionic *ionic)
 	attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
 	devlink_port_attrs_set(&ionic->dl_port, &attrs);
 	err = devlink_port_register(dl, &ionic->dl_port, 0);
-	if (err)
+	if (err) {
 		dev_err(ionic->dev, "devlink_port_register failed: %d\n", err);
-	else
-		devlink_port_type_eth_set(&ionic->dl_port,
-					  ionic->lif->netdev);
+		devlink_unregister(dl);
+		return err;
+	}
 
-	return err;
+	devlink_port_type_eth_set(&ionic->dl_port, ionic->lif->netdev);
+	return 0;
 }
 
 void ionic_devlink_unregister(struct ionic *ionic)
 {
 	struct devlink *dl = priv_to_devlink(ionic);
 
-	if (ionic->dl_port.registered)
-		devlink_port_unregister(&ionic->dl_port);
+	devlink_port_unregister(&ionic->dl_port);
 	devlink_unregister(dl);
 }