MFC r279642: Reenable VIRTIO_BLK_F_TOPOLOGY feature.
MFC r279642: Reenable VIRTIO_BLK_F_TOPOLOGY feature.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase