ACS updates

- Adapt ACS subsystem to handle events from ACS CTRL
- Some fixes and updates for ACS subsystem

linux/devices/GPSHyperionLinuxController.cpp

@@ -48,6 +48,9 @@ ReturnValue_t GPSHyperionLinuxController::checkModeCommand(Mode_t mode, Submode_
       return HasModesIF::INVALID_MODE;
     }
   }
+  if (mode == MODE_OFF) {
+    gpsSet.setValidity(false, true);
+  }
   return returnvalue::OK;
 }