RDMA/hns: Assign the value for vlan field of qp context

This patch mainly fills the correct value into the vlan id field of qp
context as well as update the vlan field name according to the latest
hardware user manual.

Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>