message: print info about perf uncore support
diff: @@ -4910,6 +4910,8 @@ bool PCM::useLinuxPerfForUncore() const
  static bool printed = false;
  bool secureBoot = isSecureBoot();
  #ifdef PCM_USE_PERF
  + const auto imcIDs = enumeratePerfPMUs("imc", 100);
  + std::cout << "INFO: Linux perf interface to program uncore PMUs is " << (imcIDs.empty()?"NOT ":"") << "present\n";
  const char * perf_env = std::getenv("PCM_USE_UNCORE_PERF");
  if (perf_env != NULL && std::string(perf_env) == std::string("1"))
  {
  