parametrize os version for gtw and cmp
diff --git a/reclass/storage/system/openstack_gateway_cluster.yml b/reclass/storage/system/openstack_gateway_cluster.yml
index 72e31c5..96ae486 100644
--- a/reclass/storage/system/openstack_gateway_cluster.yml
+++ b/reclass/storage/system/openstack_gateway_cluster.yml
@@ -17,7 +17,7 @@
           - cluster.${_param:cluster_name}.openstack.gateway
           params:
             salt_master_host: ${_param:reclass_config_master}
-            linux_system_codename: trusty
+            linux_system_codename: ${_param:linux_system_codename}
             single_address: ${_param:openstack_gateway_node01_address}
             tenant_address: ${_param:openstack_gateway_node01_tenant_address}
         openstack_gateway_node02:
@@ -37,7 +37,7 @@
           - cluster.${_param:cluster_name}.openstack.gateway
           params:
             salt_master_host: ${_param:reclass_config_master}
-            linux_system_codename: trusty
+            linux_system_codename: ${_param:linux_system_codename}
             single_address: ${_param:openstack_gateway_node03_address}
             tenant_address: ${_param:openstack_gateway_node03_tenant_address}