swim: simplify using blk_cleanup_disk() on swim_remove()

We can simplify swim_remove() by using one call instead of two,
just as other drivers do. Use that pattern.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20210927220302.1073499-8-mcgrof@kernel.org


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