RDMA/hns: Use new interface to get CQE fields

WQE_INDEX and OPCODE and QPN of CQE use redundant masks. Just remove them.

Link: https://lore.kernel.org/r/1624262443-24528-7-git-send-email-liweihang@huawei.com
Signed-off-by: Lang Cheng <chenglang@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>