RDMA/hns: Support flexible umem page size

In the current implementation, a fixed page size is used to
configure the umem PBL, which is not flexible enough and is
not conducive to the performance of the HW. Find a best page
size to get better performance.

Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Link: https://lore.kernel.org/r/20240113085935.2838701-5-huangjunxian6@hisilicon.com


Signed-off-by: Leon Romanovsky <leon@kernel.org>