iotests: Add case for a corrupted inactive image
    
    Reviewed-by: John Snow <jsnow@redhat.com>
    Tested-by: Jeff Cody <jcody@redhat.com>
    Reviewed-by: Jeff Cody <jcody@redhat.com>
    Signed-off-by: Max Reitz <mreitz@redhat.com>
    Message-id: 20180606193702.7113-4-mreitz@redhat.com
    Signed-off-by: Max Reitz <mreitz@redhat.com>
    (cherry picked from commit c50abd175a88cd41c2c08339de91f6f6e4a7b162)
    Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>