Fix raise error

git-svn-id: https://redmine.imt-atlantique.fr/svn/xaal/code/Python/trunk@1387 b32b6428-25c9-4566-ad07-03861ab6144f

xaal-lib/src/xAAL/core.py

@@ -103,6 +103,7 @@ class Engine(object):
                 msg = self.__mf.decode_msg(data)
             except MessageFactoryParserError as e:
                 logger.error(e.message)
+                msg = None
             result = msg
         return result