RDMA CM RFE : Add support for native Infiniband addressing (helps address SA scalability issues)

Issue

• The patches add the ability to handle native Infiniband addressing to the rdma_cm.
• Allowing the use of native IB addresses removes the requirement for IPoIB, which in turn allows us to offload name and/or address translation services to a user space daemon.
• The primary motivation is to support large scale fabrics, with address and name services either cached or bypassed completely.
• For example, IB GIDs are known or the information is exchanged out of band by an MPI process manager.
• However, another use case involves load balancing software.
• Currently the rdma cm cannot establish rdma connections through a load balancer, since the IP -> GID mapping is not well defined.
• An out of band mechanism could be used in such situations to determine the correct mapping, with the rdma cm still managing the connection.