blkcg: fix double free of new_blkg in blkcg_init_queue

If blkg_create fails, new_blkg passed as an argument will
be freed by blkg_create, so there is no need to free it again.

Change-Id: I35bb8601143a33f35cfcb0b1ffba6788ec184a20
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Git-commit: 9b54d816e00425c3a517514e0d677bb3cec49258
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Srinivasa Rao Kuppala <srkupp@codeaurora.org>