net: hns: fix hns dsaf v1 dont support tx_pause close

For service port, hns dsaf v1 support to close tx_pause.
However, the port will be invalid when it run command
ethtool to close tx_pause. This patch will fix it.

Signed-off-by: Qianqian Xie <xieqiaqian@huawei.com>
Signed-off-by: Yisen Zhuang <Yisen.Zhuang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>