!6942 v2 ima: fix deadlock when traversing "ima_default_rules".

Merge Pull Request from: @ci-robot 
 
PR sync from: GUO Zihua <guozihua@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/N2P5A6BT76DML34R3LB6CRZRYMEIFWX2/ 
 
https://gitee.com/openeuler/kernel/issues/I9AAM6 
 
Link:https://gitee.com/openeuler/kernel/pulls/6942

 

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