net: hns: Fix a wrong op phy C45 code

As the user manual described, the second step to write to C45 phy
by mdio should be data, but not address. Here we should fix this
issue.

Fixes: 5b904d39

 ("net: add Hisilicon Network Subsystem MDIO support")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Reviewed-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>