Update OpenVZ driver image

11.10 simply does not exist, so this simply does not work. However,
devstack-gate tries to pre-cache all images referenced, so even though
we're not doing anything with this, it's breaking devstack-gate.

Change-Id: I64b03ed387f5205a885427498e8cf8c2a5b32b91
diff --git a/stackrc b/stackrc
index 50774e4..ac72132 100644
--- a/stackrc
+++ b/stackrc
@@ -215,8 +215,8 @@
 # ``IMAGE_URLS`` to be set directly in ``localrc``.
 case "$VIRT_DRIVER" in
     openvz)
-        DEFAULT_IMAGE_NAME=${DEFAULT_IMAGE_NAME:-ubuntu-11.10-x86_64}
-        IMAGE_URLS=${IMAGE_URLS:-"http://download.openvz.org/template/precreated/ubuntu-11.10-x86_64.tar.gz"};;
+        DEFAULT_IMAGE_NAME=${DEFAULT_IMAGE_NAME:-ubuntu-12.04-x86_64}
+        IMAGE_URLS=${IMAGE_URLS:-"http://download.openvz.org/template/precreated/ubuntu-12.04.x86_64.tar.gz"};;
     libvirt)
         case "$LIBVIRT_TYPE" in
             lxc) # the cirros root disk in the uec tarball is empty, so it will not work for lxc