Handle firewall_driver option

Change-Id: I90b7c5807ecd0ea8789e17a2fd701084982d39d3
Closes-Bug: PROD-20881
diff --git a/tests/pillar/compute_legacy.sls b/tests/pillar/compute_legacy.sls
index 943b35c..1a8aa58 100644
--- a/tests/pillar/compute_legacy.sls
+++ b/tests/pillar/compute_legacy.sls
@@ -1,6 +1,7 @@
 neutron:
   compute:
     agent_mode: legacy
+    firewall_driver: noop
     backend:
       engine: ml2
       tenant_network_types: "flat,vxlan"