RDMA/hns: Remove unused RR mechanism

Round-robin (RR) is no longer used in the allocation of the bitmap table,
and all the function input parameters that use this mechanism are
BITMAP_NO_RR. The code that defines and uses the RR needs to be deleted.

Link: https://lore.kernel.org/r/1623325814-55737-4-git-send-email-liweihang@huawei.com
Signed-off-by: Yangyang Li <liyangyang20@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>