!5347 s390/ptrace: handle setting of fpc register correctly

Merge Pull Request from: @ci-robot 
 
PR sync from: Zheng Zucheng <zhengzucheng@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/YT2CJEOPDOEFDILZ3NWHD5VFY66AEQ2A/ 
 
https://gitee.com/src-openeuler/kernel/issues/I96G7Q 
 
Link:https://gitee.com/openeuler/kernel/pulls/5347

 

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