Bluetooth: unlock if allocation fails in hci_blacklist_add()

There was a small typo here so we never actually hit the goto which
would call hci_dev_unlock_bh().
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/hci_core.c

@@ -1327,7 +1327,7 @@ int hci_blacklist_add(struct hci_dev *hdev, bdaddr_t *bdaddr)
 
 	entry = kzalloc(sizeof(struct bdaddr_list), GFP_KERNEL);
 	if (!entry) {
-		return -ENOMEM;
+		err = -ENOMEM;
 		goto err;
 	}