!6661 sched/rt: sysctl_sched_rr_timeslice show default timeslice after reset

Merge Pull Request from: @ci-robot 
 
PR sync from: Cheng Yu <serein.chengyu@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/VBWUL6J73ZW6G5HBWXFWIMWFLT4IMUPD/ 
 
https://gitee.com/openeuler/kernel/issues/I9K4H3 
 
Link:https://gitee.com/openeuler/kernel/pulls/6661

 

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