block: fix deadlock between blk_mq_freeze_queue and blk_mq_dispatch_list#747

blktests-ci[bot] wants to merge 1 commit intolinus-master_baselinux-blktests/linux-block:linus-master_basefrom

series/1082402=>linus-masterlinux-blktests/linux-block:series/1082402=>linus-masterCopy head branch name to clipboard