!427 Support the feature of querying stats

Merge Pull Request from: @stinft 
 
Feature information:
1.RDMA/hns: Support hns HW stats
Support query hns HW stats to help debugging several issues.
2.RDMA/hns: Add dfx cnt stats
Add more dfx cnt to help diagnosis. And this stats could be got by
sysfs or rdmatool.
bugzilla：https://gitee.com/openeuler/kernel/issues/I6GSZL 
 
Link:https://gitee.com/openeuler/kernel/pulls/427

 

Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>