Add query for nova metadata api bug 921858

1760 fails in the last 7 days, this is 100% failure when it shows up in
the screen-n-api-meta log, looks like it's only on the
tempest-dvsm-postgres-full jobs and mostly on the stable/icehouse
branch.  Bug 1306009 might be the cause of the stable/icehouse failures
but not totally sure.

Related-Bug: #921858

Change-Id: Ifb61dc6697e8cb2d7aaadd5e1d668968e81f18e5