RDMA/hns: Delete unnecessary callback functions for cq

Currently, when cq event occurred, we first call our own callback
functions in the event process function, then call ib callback
functions. Actually, we can directly call ib callback functions.

Link: https://lore.kernel.org/r/1574044493-46984-5-git-send-email-liweihang@hisilicon.com


Signed-off-by: Yixian Liu <liuyixian@huawei.com>
Signed-off-by: Weihang Li <liweihang@hisilicon.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>