Apply template change for nbhelper refactor

Change-Id: I59f28cde629a9c73e86c020bba9b8219ee844d2d
diff --git a/templates/nftables.conf.j2 b/templates/nftables.conf.j2
index e710436..ce9ea23 100644
--- a/templates/nftables.conf.j2
+++ b/templates/nftables.conf.j2
@@ -28,10 +28,12 @@
     # Allow SSH on all interfaces
     tcp dport ssh accept
 
-    {% if "allow_subnets" in netprep_nftables %}
+    {% if "interface_subnets" in netprep_nftables %}
     # The ingress traffic restriction of internal networks
-      {% for item in netprep_nftables["allow_subnets"] %}
-    iif "{{ netprep_nftables["internal_if"] }}" ip saddr {{ item }} accept
+      {% for interface in netprep_nftables["interface_subnets"] %}
+        {% for item in netprep_nftables["interface_subnets"][interface] %}
+    iif "{{ interface }}" ip saddr {{ item }} accept
+        {% endfor %}
       {% endfor %}
     {% endif %}
   }