S57: add RECODE_BY_DSS suboption to OGR_S57_OPTIONS configuration option that can be set to YES so that the attribute values are recoded to UTF-8, from the character encoding specified in the S57 DSSI record (#5048, #3421, adapted from patch by julius6)

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@25905 f0d54148-0727-0410-94bb-9a71ac55c965