IB/core: Add rdma_network_type to wc

Providers should tell IB core the wc's network type.
This is used in order to search for the proper GID in the
GID table. When using HCAs that can't provide this info,
IB core tries to deep examine the packet and extract
the GID type by itself.

We choose sgid_index and type from all the matching entries in
RDMA-CM based on hint from the IP stack and we set hop_limit for
the IP packet based on above hint from IP stack.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Somnath Kotur <Somnath.Kotur@Avagotech.Com>
Signed-off-by: Doug Ledford <dledford@redhat.com>