OGR-VFK: fix IsPreProcessed() logic

git-svn-id: https://svn.osgeo.org/gdal/trunk@26911 f0d54148-0727-0410-94bb-9a71ac55c965
remove redundant check for units

git-svn-id: https://svn.osgeo.org/gdal/trunk@26912 f0d54148-0727-0410-94bb-9a71ac55c965
Fix short layer names in SXF driver

git-svn-id: https://svn.osgeo.org/gdal/trunk@26913 f0d54148-0727-0410-94bb-9a71ac55c965
fix minor security flaw in zlib for tiffs from un-initialized fields

git-svn-id: https://svn.osgeo.org/gdal/trunk@26914 f0d54148-0727-0410-94bb-9a71ac55c965