dlm: add missing -ENOMEM if alloc_workqueue() fails

This patch sets an missing -ENOMEM as error return value when the
allocation of the dlm workqueue fails.

Fixes: 94e180d6 ("dlm: async freeing of lockspace resources")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202408110800.OsoP8TB9-lkp@intel.com/Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

fs/dlm/main.c

@@ -53,8 +53,10 @@ static int __init init_dlm(void)
 		goto out_user;
 
 	dlm_wq = alloc_workqueue("dlm_wq", 0, 0);
-	if (!dlm_wq)
+	if (!dlm_wq) {
+		error = -ENOMEM;
 		goto out_plock;
+	}
 
 	printk("DLM installed\n");