Install libosinfo on n-cpu nodes

As of 9de8f7230d069e4da9736f09ad5d17773315b476 nova is now attempting
to import libosinfo packages, so install them for goodness sake.

Change-Id: Ib481dda475dd2975a513052478be0007aa1cf4a8
Related-Bug: #1543288
diff --git a/files/rpms/n-cpu b/files/rpms/n-cpu
index 7773b04..26c5ced 100644
--- a/files/rpms/n-cpu
+++ b/files/rpms/n-cpu
@@ -1,6 +1,7 @@
 cryptsetup
 genisoimage
 iscsi-initiator-utils
+libosinfo
 lvm2
 sg3_utils
 # Stuff for diablo volumes