Add missing file dt_pq.h that should have been committed in r239385
Add missing file dt_pq.h that should have been committed in r239385

Reported by:	Pedro Giffuni <pfg@FreeBSD.org>

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