!8773 sched: remove WARN_ON on checking rq->tmp_alone_branch

Merge Pull Request from: @ci-robot 
 
PR sync from: Hui Tang <tanghui20@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/K7FGLGGT2KLOLIQ4BF73DV2E6TDHWDZX/ 
 
https://gitee.com/openeuler/kernel/issues/I9VPMT 
 
Link:https://gitee.com/openeuler/kernel/pulls/8773

 

Reviewed-by: Liu YongQiang <liuyongqiang13@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>