add missing sort

Change-Id: I2a1536ee405be9cfdd26a4f87f30fda46a72d039
diff --git a/openstack-control-upgrade.groovy b/openstack-control-upgrade.groovy
index b121d0b..0c13b05 100644
--- a/openstack-control-upgrade.groovy
+++ b/openstack-control-upgrade.groovy
@@ -251,7 +251,7 @@
                 node_count++
             }
             def control_general_target = ""
-            def control_target_hosts = salt.getMinions(pepperEnv, 'I@keystone:server and not upg*')
+            def control_target_hosts = salt.getMinions(pepperEnv, 'I@keystone:server and not upg*').sort()
             node_count = 1
 
             for (t in control_target_hosts) {