block: don't acquire ->elevator_lock in blk_mq_map_swqueue and blk_mq_realloc_hw_ctxs

Both blk_mq_map_swqueue() and blk_mq_realloc_hw_ctxs() are called before
the request queue is added to tagset list, so the two won't run concurrently
with blk_mq_update_nr_hw_queues().

When the two functions are only called from queue initialization or
blk_mq_update_nr_hw_queues(), elevator switch can't happen.

So remove ->elevator_lock uses from the two functions.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250505141805.2751237-24-ming.lei@redhat.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>