[PATCH] nvme: don't call blk_mq_{,un}quiesce_tagset when ctrl->tagset is NULL

[Christoph Hellwig]

On Sun, Nov 20, 2022 at 01:38:28PM +0200, Sagi Grimberg wrote:
>
>>> All the other drivers check that they have IO queues before
>>> quiescing/unquiescing them.
>>
>> The core firmware activation code does not.
>
> Well, ideally it should, but maybe it would be more readable
> if we condition on ctrl->queue_count > 1.

This would be the queue_count version.  I have to say I much prefer
the tagset check, as it is self-documenting and matches what
nvme_queue_scan, nvme_cancel_tagset and nvme_cancel_admin_tagset
do.