Do not flush tunnel interface in case of TF DPDK

Related-PROD: PRODX-3811
Change-Id: Idaae564c77aa3ddd9d1898286641c3ea8c01a613
diff --git a/de/heat-templates/scripts/instance_boot.sh b/de/heat-templates/scripts/instance_boot.sh
index 2642180..dd25bf8 100644
--- a/de/heat-templates/scripts/instance_boot.sh
+++ b/de/heat-templates/scripts/instance_boot.sh
@@ -75,11 +75,13 @@
 HUGE_PAGES_2Mb_SIZE=$(echo "${HUGE_PAGES}" | awk -F ',' '{print $2}')
 CONFIGURE_HUGE_PAGES=false
 TUNNEL_INTERFACE_NETPLAN_MANAGE=true
+TUNGSTENFABRIC_ENABLED=${TUNGSTENFABRIC_ENABLED:-false}
 if [[ "${HUGE_PAGES_1G_SIZE}" -gt 0 ]] || [[ "${HUGE_PAGES_2Mb_SIZE}" -gt 0 ]]; then
     CONFIGURE_HUGE_PAGES=true
-    TUNNEL_INTERFACE_NETPLAN_MANAGE=false
+    if [[ "${TUNGSTENFABRIC_ENABLED,,}" == false ]]; then
+        TUNNEL_INTERFACE_NETPLAN_MANAGE=false
+    fi
 fi
-TUNGSTENFABRIC_ENABLED=${TUNGSTENFABRIC_ENABLED:-false}
 
 function retry {
     local retries=$1