RDMA/hns: Bugfix for the scene without receiver queue

[ Upstream commit 4d103905 ]

In some application scenario, the user could not have receive queue when
run rdma write or read operation.

Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>