RDMA/hns: Remove redundant DFX file and DFX ops structure

There is no need to use a dedicated DXF file and DFX structure to manage
the interface of the query queue context.

Link: https://lore.kernel.org/r/20220822104455.2311053-2-liangwenpeng@huawei.com


Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>