Fix gateway nodes location

Spread gateway nodes among kvm, instead of running all of
them on single host.

Change-Id: I55bc5c62620e015dd160e3cdedd9dca2f3f43dde
diff --git a/salt/control/cluster/openstack_gateway_cluster.yml b/salt/control/cluster/openstack_gateway_cluster.yml
index 5d2a20a..84c44ac 100644
--- a/salt/control/cluster/openstack_gateway_cluster.yml
+++ b/salt/control/cluster/openstack_gateway_cluster.yml
@@ -17,10 +17,10 @@
               image: ${_param:salt_control_xenial_image}
               size: openstack.gateway
             gtw02:
-              provider: kvm01.${_param:cluster_domain}
+              provider: kvm02.${_param:cluster_domain}
               image: ${_param:salt_control_xenial_image}
               size: openstack.gateway
             gtw03:
-              provider: kvm01.${_param:cluster_domain}
+              provider: kvm03.${_param:cluster_domain}
               image: ${_param:salt_control_xenial_image}
               size: openstack.gateway