!4790 v2 gfs2: Fix kernel NULL pointer dereference in gfs2_rgrp_dump

Merge Pull Request from: @ci-robot 
 
PR sync from: Baokun Li <libaokun1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/CITMLXP4NVXWUGSXRYXFZVRYR46FZSF4/ 
 
https://gitee.com/src-openeuler/kernel/issues/I932W3 
 
Link:https://gitee.com/openeuler/kernel/pulls/4790

 

Reviewed-by: Jialin Zhang <zhangjialin11@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>