GPKG: accept spatial tables whose geometry field is declared as BLOB

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@27379 f0d54148-0727-0410-94bb-9a71ac55c965
GPKG: recognize both GeomCollection and GeometryCollection as possible values, until GeoPackage SWG clears what is the official value

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@27380 f0d54148-0727-0410-94bb-9a71ac55c965