geohash code cleanup (#4787)

While analyzing the valkey coverage reports, it was observed that the
`geohashDecodeWGS84` function is dead & unreachable through any code
path

This seems to have been the case since the following commit b96af595a

---------

Signed-off-by: Bara' Hasheesh <bara.hasheesh@gmail.com>

src/geohash.c

@@ -193,10 +193,6 @@ int geohashDecodeType(const GeoHashBits hash, GeoHashArea *area) {
     return geohashDecode(r[0], r[1], hash, area);
 }
 
-int geohashDecodeWGS84(const GeoHashBits hash, GeoHashArea *area) {
-    return geohashDecodeType(hash, area);
-}
-
 int geohashDecodeAreaToLongLat(const GeoHashArea *area, double *xy) {
     if (!xy) return 0;
     xy[0] = (area->longitude.min + area->longitude.max) / 2;

src/geohash.h

@@ -131,7 +131,6 @@ int geohashDecode(const GeoHashRange long_range,
                   const GeoHashBits hash,
                   GeoHashArea *area);
 int geohashDecodeType(const GeoHashBits hash, GeoHashArea *area);
-int geohashDecodeWGS84(const GeoHashBits hash, GeoHashArea *area);
 int geohashDecodeAreaToLongLat(const GeoHashArea *area, double *xy);
 int geohashDecodeToLongLatType(const GeoHashBits hash, double *xy);
 int geohashDecodeToLongLatWGS84(const GeoHashBits hash, double *xy);