Revert "Refactor mechanism driver metadata"

This reverts commit 79ffa26858d682f404984175dc1ab93863a149ad.

Fixes PROD-14994

Change-Id: I8dc05999dd072b3249831a7ef01d07831e46db0f
diff --git a/tests/pillar/control_nodvr.sls b/tests/pillar/control_nodvr.sls
index 00a261c..9597eee 100644
--- a/tests/pillar/control_nodvr.sls
+++ b/tests/pillar/control_nodvr.sls
@@ -4,8 +4,8 @@
       engine: ml2
       external_mtu: 1500
       mechanism:
-        - openvswitch
-        - l2population
+        ovs:
+          driver: openvswitch
       tenant_network_types: flat,vxlan
     bind:
       address: 172.16.10.101