net: hns3: bugfix for hclge_mdio_write and hclge_mdio_read

When there is a PHY, the driver needs to complete some operations through
MDIO during reset reinitialization, so HCLGE_STATE_CMD_DISABLE is more
suitable than HCLGE_STATE_RST_HANDLING to prevent the MDIO operation from
being sent during the hardware reset.

Fixes: b50ae26c

 ("net: hns3: never send command queue message to IMP when reset)
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>