[linux] Apply MAC address prior to registering network device

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/drivers/linux/tap.c

 	netdev->dev = &device->dev;
 	memset(nic, 0, sizeof(*nic));
 
-	if ((rc = register_netdev(netdev)) != 0)
-		goto err_register;
-
-	netdev_link_up(netdev);
-
 	/* Look for the mandatory if setting */
 	if_setting = linux_find_setting("if", &request->settings);
 
 	/* Apply rest of the settings */
 	linux_apply_settings(&request->settings, &netdev->settings.settings);
 
+	/* Register network device */
+	if ((rc = register_netdev(netdev)) != 0)
+		goto err_register;
+
+	netdev_link_up(netdev);
+
 	return 0;
 
 err_settings: