When blk_throtl_init fails, we need to call blk_ioprio_exit.  Switch to
proper goto based unwinding to fix this.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220921180501.1539876-2-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>