Add genisoimage as dependency

Fixes bug 1076854

Change-Id: I51cd293898f40edaf241a2fb7aff27e73f3a8e07
diff --git a/files/rpms/n-cpu b/files/rpms/n-cpu
index 1996a98..f7054e8 100644
--- a/files/rpms/n-cpu
+++ b/files/rpms/n-cpu
@@ -1,3 +1,4 @@
 # Stuff for diablo volumes
 iscsi-initiator-utils
 lvm2
+genisoimage