Use Spin locks on Tile

On Tile, replace pthread_mutex_locks with queued spin locks (ticket
locks) for dataplane processing code. This is safe when running on
dataplane cores with one thread per core. The condition variables are
no-ops when the thread is spinning anyway.

For control plane threads, unix-manager, stats-logs, thread startup,
use pthread_mutex_locks. For these locks replaced SCMutex with SCCtrlMutex
and SCCond with SCCtrlCond.
Split Thresholds and Suppression

Thresholds and suppression can be handled independently. Suppression
only suppresses output, and is not related to Threshold state tracking.

This simplifies mixing suppression and thresholding rules.

Part of the Bug #425 effort.
Thresholding: move parsing code into separate func
Stateful detection inspection continuation API call should update per
signature's Sigmatch entry as well.