add ipflush_onchange for ens4 interface

Change-Id: I01325ff4144ed83e49eedd0b776ec159929be749
diff --git a/classes/cluster/k8s_ha_contrail/kubernetes/compute.yml b/classes/cluster/k8s_ha_contrail/kubernetes/compute.yml
index 4cad082..2d0b775 100644
--- a/classes/cluster/k8s_ha_contrail/kubernetes/compute.yml
+++ b/classes/cluster/k8s_ha_contrail/kubernetes/compute.yml
@@ -13,6 +13,7 @@
           enabled: true
           type: eth
           proto: manual
+          ipflush_onchange: true
         vhost0:
           enabled: true
           type: eth