block: fix docs for freezing of queue limits updates

queue_limits_commit_update is the function that needs to operate on a
frozen queue, not queue_limits_start_update.  Update the kerneldoc
comments to reflect that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20250110054726.1499538-2-hch@lst.de


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