Cleanup of unused and outdated legacy RFSIM code

- deleted:    ../../../executables/rfsim.c
- removed unused command line options to set SINR and SNR
- removed unused functions to get SINR and SNR
- removed unused RFSIM struct members

radio/rfsimulator/simulator.c

@@ -206,17 +206,6 @@ static int allocCirBuf(rfsimulator_state_t *bridge, int sock)
 
   if ( bridge->channelmod > 0) {
     // create channel simulation model for this mode reception
-    // snr_dB is pure global, coming from configuration paramter "-s"
-    // Fixme: referenceSignalPower should come from the right place
-    // but the datamodel is inconsistant
-    // legacy: RC.ru[ru_id]->frame_parms.pdsch_config_common.referenceSignalPower
-    // (must not come from ru[]->frame_parms as it doesn't belong to ru !!!)
-    // Legacy sets it as:
-    // ptr->channel_model->path_loss_dB = -132.24 + snr_dB - RC.ru[0]->frame_parms->pdsch_config_common.referenceSignalPower;
-    // we use directly the paramter passed on the command line ("-s")
-    // the value channel_model->path_loss_dB seems only a storage place (new_channel_desc_scm() only copy the passed value)
-    // Legacy changes directlty the variable channel_model->path_loss_dB place to place
-    // while calling new_channel_desc_scm() with path losses = 0
     static bool init_done=false;
 
     if (!init_done) {