Exit GetPadDetailForIdx after processing null reference

Might be related to issue #326.

DS4Windows/DS4Control/ControlService.cs

@@ -64,7 +64,7 @@ namespace DS4Windows
                 meta.Model = DsModel.None;
                 meta.BatteryStatus = 0;
                 meta.IsActive = false;
-
+                return;
                 //return meta;
             }