RDMA/hns: Optimize qp context create and destroy flow

Rename the qp context related functions and adjusts the code location to
distinguish between the qp context and the entire qp.

Link: https://lore.kernel.org/r/1582526258-13825-3-git-send-email-liweihang@huawei.com


Signed-off-by: Xi Wang <wangxi11@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>