Add Debian OS support in DevStack

Fix bug #1176216

Change-Id: Ia94c332f02a921a936db249dc3b4a7ae4eff0400
diff --git a/files/apts/n-cpu b/files/apts/n-cpu
index ef281ca..88e0144 100644
--- a/files/apts/n-cpu
+++ b/files/apts/n-cpu
@@ -2,7 +2,7 @@
 nbd-client
 lvm2
 open-iscsi
-open-iscsi-utils
+open-iscsi-utils # Deprecated since quantal dist:lucid,oneiric,precise
 genisoimage
 sysfsutils
 sg3-utils