message: Fix timing output
  The timing output was printing the same times for different tunings.
  Fix getVariantTuningIndex to return the correct index
  instead of always returning 0.
diff: @@ -129,16 +129,17 @@ public:
  }
  size_t getVariantTuningIndex(VariantID vid, std::string const& tuning_name) const
  {
  - size_t t = 0;
  - for (std::string const& a_tuning_name : getVariantTuningNames(vid)) {
  + std::vector<std::string> const& tuning_names = getVariantTuningNames(vid);
  + for (size_t t = 0; t < tuning_names.size(); ++t) {
  + std::string const& a_tuning_name = tuning_names[t];
  if (tuning_name == a_tuning_name) { return t; }
  }
  return getUnknownTuningIdx();
  }
  size_t getNumVariantTunings(VariantID vid) const
  - { return variant_tuning_names[vid].size(); }
  + { return getVariantTuningNames(vid).size(); }
  std::string const& getVariantTuningName(VariantID vid, size_t tid) const
  - { return variant_tuning_names[vid].at(tid); }
  + { return getVariantTuningNames(vid).at(tid); }
  std::vector<std::string> const& getVariantTuningNames(VariantID vid) const
  { return variant_tuning_names[vid]; }
  