All RDMA ULPs should be using rdma_get_gid_attr instead of
ib_query_gid. Convert SMC to use the new API.

In the process correct some confusion with gid_type - if attr->ndev is
!NULL then gid_type can never be IB_GID_TYPE_IB by
definition. IB_GID_TYPE_ROCE shares the same enum value and is probably
what was intended here.
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>