change volume name template to prepare for 6511

Change-Id: I1162c169eeffbd9adf9cfb9f473761d6f8b2d120
diff --git a/stack.sh b/stack.sh
index 71c5ffc..a7891af 100755
--- a/stack.sh
+++ b/stack.sh
@@ -1526,7 +1526,7 @@
 fi
 if is_service_enabled n-vol; then
     add_nova_opt "volume_group=$VOLUME_GROUP"
-    add_nova_opt "volume_name_template=${VOLUME_NAME_PREFIX}%08x"
+    add_nova_opt "volume_name_template=${VOLUME_NAME_PREFIX}%s"
     # oneiric no longer supports ietadm
     add_nova_opt "iscsi_helper=tgtadm"
 fi