block: Move a misplaced comment in queue_wb_lat_store()

block: Move a misplaced comment in queue_wb_lat_store()

blk_mq_quiesce_queue() does not wait for pending I/O to finish. Freezing
a queue waits for pending I/O to finish. Hence move the comment that
refers to waiting for pending I/O above the call that freezes the
request queue. This patch moves this comment back to the position where
it was when this comment was introduced. See also commit c125311d96b1
("blk-wbt: don't maintain inflight counts if disabled").

Cc: Christoph Hellwig <hch@lst.de>
Cc: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20250825151424.1653910-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>