mlz/demo: move old examples to Attached

change very early version of module attachments in GarfieldMagnet and
MagnetigField to use Attached

Change-Id: I616ad17bc72cd93d86e1b3e3609543cfe90edcd8
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/32250
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>

cfg/demo_cfg.py

@@ -41,6 +41,6 @@ Mod('label',
     'frappy_demo.modules.Label',
     'some label indicating the state of the magnet `mf`.',
     system = 'Cryomagnet MX15',
-    subdev_mf = 'mf',
-    subdev_ts = 'ts',
+    mf = 'mf',
+    ts = 'ts',
 )