report POSTFIELDS through debug too

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@26220 f0d54148-0727-0410-94bb-9a71ac55c965
fix POSTFIELDS debug formatting

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@26221 f0d54148-0727-0410-94bb-9a71ac55c965