Export list of hwthreads to wrapped application
Created by: TomTheBear
This PR adds the export of the used HW threads through the environment variable LIKWID_HWTHREADS
so that applications can use this knowledge. There is already an environment variable LIKWID_THREADS
but it only exported by likwid-perfctr
in MarkerAPI mode. In some cases, you need the knowledge also in non-instrumented applications.