Un-hardcoding apache address

The patch un-hardcodes IP address which can be
used to be bound for apache while redirect.

Change-Id: Iedf513c375896d5d651fc5462fa70edaf27ce779
diff --git a/defaults/openstack/init.yml b/defaults/openstack/init.yml
index f04809f..69ff618 100644
--- a/defaults/openstack/init.yml
+++ b/defaults/openstack/init.yml
@@ -51,6 +51,7 @@
     # Apache mods defaults
     apache_mods_status_enabled: True
     apache_mods_status_status: 'disabled'
+    apache_horizon_listen_address: '0.0.0.0'
     # Horizon
     # 'direct' mode will require cors on glance side to be enabled.
     horizon_images_upload_mode: 'direct'