net: hns3: add barrier in vf mailbox reply process

driver inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7OQCS


CVE: NA

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

In hclgevf_mbx_handler() and hclgevf_get_mbx_resp() functions,
there is a typical store-store and load-load scenario between
received_resp and additional_info. This patch adds barrier
to fix the problem.

Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>