Fix for regression from PR#3962
    
    There was a regression caused in nightly run of test
    TestBackupReinstallRestoreWithDNS of test_backup_and_restore
    test suite because of PR#3962.
    
    Signed-off-by: Kaleemullah Siddiqui <ksiddiqu@redhat.com>
    Reviewed-By: Florence Blanc-Renaud <flo@redhat.com>