bcache: bset: Fix comment typos

Remove the redundant word `by`, correct the typo `creaated`.

CC: Kent Overstreet <kent.overstreet@gmail.com>
CC: linux-bcache@vger.kernel.org
Signed-off-by: Jules Maselbas <jmaselbas@kalray.eu>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20220919161647.81238-4-colyli@suse.de


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