Fix for the non-working PAPI_stop_counters. It turned out that PAPI_stop_counters called PAPI_num_counters which in turn always allocated a new event set for the high-level substrate.
Fix for the non-working PAPI_stop_counters. It turned out that
PAPI_stop_counters called PAPI_num_counters which in turn always
allocated a new event set for the high-level substrate.

pyrovski/papi,pyrovski/papi,arm-hpc/papi,arm-hpc/papi,arm-hpc/papi,arm-hpc/papi,arm-hpc/papi,pyrovski/papi,pyrovski/papi,pyrovski/papi,arm-hpc/papi,pyrovski/papi,pyrovski/papi,arm-hpc/papi,pyrovski/papi