umem: don't override the queue_lock

The umem card->lock and the block layer queue_lock are used for entirely
different resources.  Stop using card->lock as the block layer
queue_lock.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/umem.c

@@ -888,8 +888,7 @@ static int mm_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	card->biotail = &card->bio;
 	spin_lock_init(&card->lock);
 
-	card->queue = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE,
-					   &card->lock);
+	card->queue = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE, NULL);
 	if (!card->queue)
 		goto failed_alloc;