make CMake aware of possible OSGeo4W64 installation path
make CMake aware of possible OSGeo4W64 installation path

mtCarto/PDAL,jwomeara/PDAL,jwomeara/PDAL,DougFirErickson/PDAL,mtCarto/PDAL,jwomeara/PDAL,Sciumo/PDAL,boundlessgeo/PDAL,jwomeara/PDAL,DougFirErickson/PDAL,mpgerlek/PDAL-old,verma/PDAL,Sciumo/PDAL,verma/PDAL,verma/PDAL,Sciumo/PDAL,lucadelu/PDAL,radiantbluetechnologies/PDAL,Sciumo/PDAL,lucadelu/PDAL,verma/PDAL,radiantbluetechnologies/PDAL,boundlessgeo/PDAL,mtCarto/PDAL,mpgerlek/PDAL-old,mpgerlek/PDAL-old,verma/PDAL,radiantbluetechnologies/PDAL,radiantbluetechnologies/PDAL,boundlessgeo/PDAL,lucadelu/PDAL,DougFirErickson/PDAL,lucadelu/PDAL,verma/PDAL,verma/PDAL,mtCarto/PDAL,DougFirErickson/PDAL,mpgerlek/PDAL-old,boundlessgeo/PDAL