!7963 ipv6: Fix infinite recursion in fib6_dump_done().

Merge Pull Request from: @ci-robot 
 
PR sync from: Zhengchao Shao <shaozhengchao@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/3ZKSRSIFQ2XA6VWNB4K4XMW4PJ7FTM25/ 
 
https://gitee.com/src-openeuler/kernel/issues/I9QG76 
 
Link:https://gitee.com/openeuler/kernel/pulls/7963

 

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