devlink: Prevent port_type_set() callback when it's not needed

When a port_type_set() is been called and the new port type set is the same
as the old one, just return success.

Signed-off-by: Elad Raz <eladr@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/devlink.c

@@ -608,6 +608,8 @@ static int devlink_port_type_set(struct devlink *devlink,
 	if (devlink->ops && devlink->ops->port_type_set) {
 		if (port_type == DEVLINK_PORT_TYPE_NOTSET)
 			return -EINVAL;
+		if (port_type == devlink_port->type)
+			return 0;
 		err = devlink->ops->port_type_set(devlink_port, port_type);
 		if (err)
 			return err;