RDMA/hns: Support getting max QP number from firmware

All functions of HIP09's ROCEE share on-chip resources for all QPs, the
driver needs configure the resource index and number for each function
during the init stage.

Link: https://lore.kernel.org/r/1622541427-42193-1-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@nvidia.com>