nvme-multipath: set nr_zones for zoned namespaces

The bio based drivers only require the request_queue's nr_zones is set,
so set this field in the head if the namespace path is zoned.

Fixes: 240e6ee2 ("nvme: support for zoned namespaces")
Reported-by: Minwoo Im <minwoo.im.dev@gmail.com>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/multipath.c

@@ -677,6 +677,10 @@ void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id)
 	if (blk_queue_stable_writes(ns->queue) && ns->head->disk)
 		blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES,
 				   ns->head->disk->queue);
+#ifdef CONFIG_BLK_DEV_ZONED
+	if (blk_queue_is_zoned(ns->queue) && ns->head->disk)
+		ns->head->disk->queue->nr_zones = ns->queue->nr_zones;
+#endif
 }
 
 void nvme_mpath_remove_disk(struct nvme_ns_head *head)