
add support to _papi_hwd_enum_events;
made changes to accomodate the updates in papi_preset.c;
tune the interface to call _papi_hwi_dispatch_overflow_signal;

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