include state FIPS codes in set of all FIPS geo values

so that `delphi_utils.geomap.GeoMapper().get_geo_values('fips')` also includes (for example) "42000" representing all of Pennsylvania, in addition to FIPS codes in the 42001-42999 interval that represent individual counties.

see discussion at cmu-delphi/delphi-epidata#1134

Author: melange396

_delphi_utils_python/delphi_utils/geomap.py

@@ -158,7 +158,7 @@ def _load_geo_values(self, geo_type):
             to_code = from_code = "state"
         elif geo_type == "fips":
             from_code = "fips"
-            to_code = "pop"
+            to_code = "state"
         else:
             from_code = "fips"
             to_code = geo_type