Check if openshift_master_ingress_ip_network_cidr is defined

Signed-off-by: Mathias Merscher <Mathias.Merscher@dg-i.net>

roles/openshift_master/templates/master.yaml.v1.j2

@@ -164,7 +164,7 @@ networkConfig:
 # serviceNetworkCIDR must match kubernetesMasterConfig.servicesSubnet
   serviceNetworkCIDR: {{ openshift.common.portal_net }}
   externalIPNetworkCIDRs: {{ openshift_master_external_ip_network_cidrs | default(["0.0.0.0/0"]) | to_padded_yaml(1,2) }}
-{% if openshift_master_ingress_ip_network_cidr %}
+{% if openshift_master_ingress_ip_network_cidr is defined %}
   ingressIPNetworkCIDR: {{ openshift_master_ingress_ip_network_cidr }}
 {% endif %}
 oauthConfig: