Fixed stc-cell-repair to properly prune atomix cluster nodes as well.

Change-Id: I1470512ae6e2cef4885907d9aa10edab1b05abaf
diff --git a/tools/test/bin/stc-cell-repair b/tools/test/bin/stc-cell-repair
index ad91eaa..85322ca 100755
--- a/tools/test/bin/stc-cell-repair
+++ b/tools/test/bin/stc-cell-repair
@@ -13,7 +13,7 @@
 # Destroy all cell-related containers on the specified slave; do not touch
 # the base-* template images though.
 ssh sdn@$slave "
-    containers=\$(sudo lxc-ls --fancy | grep -E '[a-z]*-[0-9n]' | cut -d\  -f1)
+    containers=\$(sudo lxc-ls --fancy | grep -E '[a-z]*-[0-9cn]' | cut -d\  -f1)
     for c in \$containers; do
         sudo lxc-stop -n \$c
         sudo lxc-destroy -n \$c