archivemxfinfo: move variable decls to top of function
archivemxfinfo: move variable decls to top of function

ebu/ebu-libmxf,stuarthicks/libmxf,Limecraft/ebu-libmxf,stuarthicks/libmxf,ebu/ebu-libmxf,ebu/ebu-libmxf,Limecraft/ebu-libmxf,ebu/ebu-libmxf,stuarthicks/libmxf,Limecraft/ebu-libmxf,stuarthicks/libmxf