block, bfq: factor out code to update 'active_entities'

Current code is a bit ugly and hard to read.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Paolo Valente <paolo.valente@unimore.it>
Link: https://lore.kernel.org/r/20221102022542.3621219-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 file changed