VFK: improve handling of data records in the header (see r27621)
     handle also duplicated records


git-svn-id: https://svn.osgeo.org/gdal/trunk@27625 f0d54148-0727-0410-94bb-9a71ac55c965
VFK driver: fix typo in comment (based on VFK documentation)

git-svn-id: https://svn.osgeo.org/gdal/trunk@27626 f0d54148-0727-0410-94bb-9a71ac55c965