net/hns3: limit promiscuous mode for VF

net/hns3: limit promiscuous mode for VF

For Kunpeng920, both tx and rx promisc is set when the promisc mode
is enabled. In other words, all the ingress packets and the packets sent
from the PF and other VFs on the same physical port will be copied
to the function which set promisc mode on.

Kunpeng930 support to turn off the tx unicast promisc. A limit promisc
mode is introduced, which means turn off the tx unicast promisc when
promisc is set.

Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
Signed-off-by: Lijun Ou <oulijun@huawei.com>