Add support for <role>_ingress_class_name

Change-Id: I7b37dda12036e7a9e0ada33fdfe6d45511b0ee18
(cherry picked from commit c139abc1d338f923ab5d528460d2f4906b78e2e2)
diff --git a/roles/glance/defaults/main.yml b/roles/glance/defaults/main.yml
index 5d9dc6e..50025d2 100644
--- a/roles/glance/defaults/main.yml
+++ b/roles/glance/defaults/main.yml
@@ -19,6 +19,9 @@
 glance_helm_release_namespace: openstack
 glance_helm_values: {}
 
+# Class name to use for the Ingress
+glance_ingress_class_name: "{{ atmosphere_ingress_class_name }}"
+
 # List of annotations to apply to the Ingress
 glance_ingress_annotations: {}