displayconfig: perform hidl_cb for default switch case

Change-Id: Iff191b7278840e39aedd68f2436368e6453cdcd6
CRs-Fixed: 2777786
diff --git a/services/config/src/device_impl.cpp b/services/config/src/device_impl.cpp
index b097006..92e5183 100644
--- a/services/config/src/device_impl.cpp
+++ b/services/config/src/device_impl.cpp
@@ -937,6 +937,7 @@
       client->ParseIsRCSupported(input_params, _hidl_cb);
       break;
     default:
+      _hidl_cb(-EINVAL, {}, {});
       break;
   }
   return Void();