RDMA/hns: Fix refcount leak in hns_roce_mmap

RDMA/hns: Fix refcount leak in hns_roce_mmap

[ Upstream commit cf6a05c8494a8ae7fec8e5f1229b45ca5b4bcd30 ]

rdma_user_mmap_entry_get_pgoff() takes the reference.
Add missing rdma_user_mmap_entry_put() to release the reference.

Fixes: 0045e0d3f42e ("RDMA/hns: Support direct wqe of userspace")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Acked-by Haoyue Xu <xuhaoyue1@hisilicon.com>
Link: https://lore.kernel.org/r/20221223072900.802728-1-linmq006@gmail.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>