added system.linux.system.repo.mcp.salt where missing

Change-Id: Iec33efa97a7638437ddfe280ec3f2c69889e791f
diff --git a/classes/cluster/drivetrain-ha-clusters/infra/config.yml b/classes/cluster/drivetrain-ha-clusters/infra/config.yml
index a96d9fe..d5467bc 100644
--- a/classes/cluster/drivetrain-ha-clusters/infra/config.yml
+++ b/classes/cluster/drivetrain-ha-clusters/infra/config.yml
@@ -1,4 +1,5 @@
 classes:
+  - system.linux.system.repo.mcp.salt
   - system.salt.master.pkg
   - system.salt.master.api
   - system.salt.minion.ca.salt_master