Emergency fix for virttooling pxeswitch errors.
Emergency fix for virttooling pxeswitch errors.

This fixes an issue with the change-management code when called with
host principals -- currently fails with a 404 error when the host being
built attempts to pxeswitch itself using the host principal (reported
on aqd-eng).

Change-Id: Ia7bb1193b8e4418076bb4bb5aa75d2b341571741
Addresses-Issue: Jira/AQUILON-4280
Reviewed-By: Dave Reeve <6a84ee3ae0690d4584b99406fb3076392171f50e@morganstanley.com>

quattor/aquilon,quattor/aquilon,quattor/aquilon