- don't process CMA and DFE if they are not selected
- ToDo: encapsulate DFE-on and DFE-off in one class. Always feed X to prevent switch artifacts
git-svn-id: http://moon:8086/svn/software/trunk/projects/mpsk_rx_gui@103 b431acfa-c32f-4a4a-93f1-934dc6c82436