net: hns: fixes a bug about timeout by pause frame

this patch fixes the bug triggered timeout sequence. when the connective
ports cannot accept the packets with higher speed, they will send out the
pause frame to the Soc's mac. At that time, the driver resets the relevant
of the Soc, then it causes the packets cannot be sent out immediately.
this patch fixes the issue.

Signed-off-by: yankejian <yankejian@huawei.com>
Signed-off-by: Yisen Zhuang <yisen.zhuang@huawei.com>
Signed-off-by: lisheng <lisheng011@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>