block: add a bio_chain_and_submit helper

This is basically blk_next_bio just with the bio allocation moved
to the caller to allow for more flexible bio handling in the caller.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240506042027.2289826-4-hch@lst.de


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