net: hns3: add handling vlan tag offload in bd

This patch deals with the vlan tag information between
sk_buff and rx/tx bd.

Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>