Have SampleAgg::sample_region handle special hashes
Have SampleAgg::sample_region handle special hashes

- This allows the Reporter to use the same function for regions, epoch
  totals, and app totals.

Signed-off-by: Diana Guttman <98d11df29868673c9a01b97a41154316626a31b0@intel.com>

geopm/geopm,cmcantalupo/geopm,geopm/geopm,cmcantalupo/geopm,cmcantalupo/geopm,cmcantalupo/geopm,geopm/geopm,cmcantalupo/geopm,geopm/geopm,geopm/geopm