SCHWED-882: tested that OpenMM CPU-platform-failure is properly caught with ext. force fields

modelling/pymod/_pipeline.py

@@ -123,16 +123,13 @@ def _SetupMmSimulation(model, force_fields):
     # finally set up the simulation
     try:
         # use fast CPU platform by default
+        # NOTE: settings.platform only relevant for mm.Simulation!
         settings.platform = mm.Platform.CPU
         num_cpu_threads = os.getenv('PM3_OPENMM_CPU_THREADS')
         if num_cpu_threads is None:
             settings.cpu_properties["CpuThreads"] = "1"
         else:
             settings.cpu_properties["CpuThreads"] = num_cpu_threads
-        
-        # TODO: check when platform problem appears when having multiple 
-        #       topologies! -> should be here
-
         sim = mm.Simulation(top, ent, settings)
     except RuntimeError as ex:
         ost.LogWarning("OpenMM failed to initialize with error: %s" % str(ex))