nvme-fc: fix module_init (theoretical) error path

If nvmf_register_transport happened to fail
(it can't, but theoretically) we leak memory.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

drivers/nvme/host/fc.c

@@ -2546,11 +2546,20 @@ static struct nvmf_transport_ops nvme_fc_transport = {
 
 static int __init nvme_fc_init_module(void)
 {
+	int ret;
+
 	nvme_fc_wq = create_workqueue("nvme_fc_wq");
 	if (!nvme_fc_wq)
 		return -ENOMEM;
 
-	return nvmf_register_transport(&nvme_fc_transport);
+	ret = nvmf_register_transport(&nvme_fc_transport);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	destroy_workqueue(nvme_fc_wq);
+	return ret;
 }
 
 static void __exit nvme_fc_exit_module(void)