4.1.1 Correct fail message for sanity infra tests

Correct message in sanity infrastructure tests
In case if there is no compute nodes

Change-Id: Ib6f9e21c5bc3a1885a065005ba3807771f1550ee
Closes-Bug: #1288660
Merge "4.1.1 Correct fail message for sanity infra tests" into stable/4.1