Fix for CYGWIN which resolves undefined references

If building under cygwin, you'll encounter the following undefined references:

build_geometry.o: In function `coords2nodes':
/cygdrive/c/development/bamboo/bamboo-home/xml-data/build-dir/OSM-OSM2PSQL-JOB1/build_geometry.cpp:220: undefined reference to `geos::geom::Coordinate::Coordinate(double, double, double)'
/cygdrive/c/development/bamboo/bamboo-home/xml-data/build-dir/OSM-OSM2PSQL-JOB1/build_geometry.cpp:220: undefined reference to `geos::geom::Coordinate::~Coordinate()'
/cygdrive/c/development/bamboo/bamboo-home/xml-data/build-dir/OSM-OSM2PSQL-JOB1/build_geometry.cpp:220: undefined reference to `geos::geom::Coordinate::~Coordinate()'

This update resolves those issues.