net: hns3: remove redundant param to simplify code

The param msg_q is redundant, copy &req->msg to
hdev->arq.msg_q[hdev->arq.tail] directly makes code clean.
So removes the redundant param msg_q.

Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>