staging: vme_user: fix root device leak on init failure

Make sure to deregister and free the root device in case module
initialisation fails.

Fixes: 658bcdae9c ("vme: Adding Fake VME driver")
Cc: stable@vger.kernel.org	# 4.9
Cc: Martyn Welch <martyn@welchs.me.uk>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260424104910.2619349-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vme_user/vme_fake.c

@@ -1230,6 +1230,8 @@ err_master:
 err_driver:
 	kfree(fake_bridge);
 err_struct:
+	root_device_unregister(vme_root);
+
 	return retval;
 }