Fix opencontrail/meta/*.yml for the CI

Change-Id: Ic3ab764c2104c1a3ee5703137a99de7d4b8b6029
diff --git a/metadata.yml b/metadata.yml
index 9ae0df6..ba3b2d8 100644
--- a/metadata.yml
+++ b/metadata.yml
@@ -3,4 +3,6 @@
 source: "https://github.com/openstack/salt-formula-opencontrail"
 dependencies:
 - name: linux
-  source: "https://github.com/tcpcloud/salt-formula-linux"
+  source: "https://github.com/salt-formulas/salt-formula-linux"
+- name: prometheus
+  source: "https://github.com/salt-formulas/salt-formula-prometheus"