Rework Tile CPU affinity setting to handle non-contiguous sets of CPUs.

It is possible to have a non-contiguous CPU set, which was not being
handled correctly on the TILE architecture.

Added a "rank" field in the ThreadVar to store the worker's rank separately
from the cpu for this case.

passes PR script:
- PR pcaps: https://buildbot.suricata-ids.org/builders/ken-tilera-pcap/builds/71
- PR build: https://buildbot.suricata-ids.org/builders/ken-tilera/builds/137