bio_alloc_bioset references current->bio_list[1], so we need to
initialize it for the blk-mq submission path as well.

Fixes: ff93ea0c ("block: shortcut __submit_bio_noacct for blk-mq drivers")
Reported-by: NQian Cai <cai@lca.pw>
Reported-by: NNaresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NNaresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>