net: hns3: Set STATE_DOWN bit of hdev state when stopping net

net: hns3: Set STATE_DOWN bit of hdev state when stopping net

We clear STATE_DOWN bit of hdev state when starting net, but do not set
it again when stopping net. It causes that the net is down, but hdev state
is still up. STATE_DOWN bit of hdev state should be set when stopping net.

Fixes: 46a3df9f9718 ("net: hns3: Add HNS3 Acceleration Engine & Compatibility Layer Support")
Fixes: e2cb1dec9779 ("net: hns3: Add HNS3 VF HCL(Hardware Compatibility Layer) Support")
Signed-off-by: Fuyun Liang <liangfuyun1@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>