++ nest ingressgateway service override under internal defaults key

infrastructure/istio-gateway/vad/istio-gateway.yaml

@@ -12,20 +12,21 @@ spec:
     - name: istiod
       namespace: istio-system
   values:
-    service:
-      type: NodePort
-      ports:
-        - name: status-port
-          port: 15021
-          protocol: TCP
-          targetPort: 15021
-        - name: http2
-          port: 80
-          protocol: TCP
-          targetPort: 80
-          nodePort: 30080
-        - name: https
-          port: 443
-          protocol: TCP
-          targetPort: 443
-          nodePort: 30443
+    _internal_defaults_do_not_set:
+      service:
+        type: NodePort
+        ports:
+          - name: status-port
+            port: 15021
+            protocol: TCP
+            targetPort: 15021
+          - name: http2
+            port: 80
+            protocol: TCP
+            targetPort: 80
+            nodePort: 30080
+          - name: https
+            port: 443
+            protocol: TCP
+            targetPort: 443
+            nodePort: 30443