Parameterized linux_system_codename

Change-Id: Ic527bfa74b4caf7e0bb5d157bfae024f2cf53111
diff --git a/reclass/storage/system/stacklight_server_cluster.yml b/reclass/storage/system/stacklight_server_cluster.yml
index 26b9ebe..4846c84 100644
--- a/reclass/storage/system/stacklight_server_cluster.yml
+++ b/reclass/storage/system/stacklight_server_cluster.yml
@@ -3,6 +3,7 @@
     stacklight_monitor_node01_hostname: mon01
     stacklight_monitor_node02_hostname: mon02
     stacklight_monitor_node03_hostname: mon03
+    stacklight_monitor_system_codename: xenial
   reclass:
     storage:
       node:
@@ -18,10 +19,9 @@
             redis_cluster_role: 'master'
             rabbitmq_cluster_role: 'master'
             salt_master_host: ${_param:reclass_config_master}
-            linux_system_codename: xenial
+            linux_system_codename: ${_param:stacklight_monitor_system_codename}
             single_address: ${_param:stacklight_monitor_node01_address}
             keepalived_vip_priority: 103
-            rabbitmq_cluster_role: master
         stacklight_server_node02:
           name: ${_param:stacklight_monitor_node02_hostname}
           domain: ${_param:cluster_domain}
@@ -31,10 +31,9 @@
             redis_cluster_role: 'slave'
             rabbitmq_cluster_role: 'slave'
             salt_master_host: ${_param:reclass_config_master}
-            linux_system_codename: xenial
+            linux_system_codename: ${_param:stacklight_monitor_system_codename}
             single_address: ${_param:stacklight_monitor_node02_address}
             keepalived_vip_priority: 102
-            rabbitmq_cluster_role: slave
         stacklight_server_node03:
           name: ${_param:stacklight_monitor_node03_hostname}
           domain: ${_param:cluster_domain}
@@ -44,7 +43,6 @@
             redis_cluster_role: 'slave'
             rabbitmq_cluster_role: 'slave'
             salt_master_host: ${_param:reclass_config_master}
-            linux_system_codename: xenial
+            linux_system_codename: ${_param:stacklight_monitor_system_codename}
             single_address: ${_param:stacklight_monitor_node03_address}
             keepalived_vip_priority: 101
-            rabbitmq_cluster_role: slave