net: hns3: add trace event support for PF/VF mailbox

mainline inclusion
from mainline-v5.8-rc1
commit d8355240
category: feature
bugzilla: NA
CVE: NA

----------------------------

This patch adds trace event support for PF/VF mailbox.

Signed-off-by: Yufeng Mo <moyufeng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Reviewed-by: Yongxin Li <liyongxin1@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>