FROMGIT: block/blk-cgroup: Swap the blk_throtl_init() and blk_iolatency_init() calls

Before adding more calls in this function, simplify the error path.

Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
BUG: 187357408
Change-Id: I8568b87d1bebbd3841e42a79b7efe2d0a1bff2bc
(cherry picked from commit f1a7f539c2720906fb10be0af3514b034e1a9fee git://git.kernel.dk/linux-block/

 for-5.14/block)
Signed-off-by: Bart Van Assche <bvanassche@google.com>