Ticket 47548 - register-ds-admin - silent file incorrectly processed
    
    Bug Description:  There was an improper check to see if any "instances"
                      were set in the INF file.  THis lead to an erroneous
                      error.
    
    FIx Description:  Check that the instance array actually has elements.
    
    https://fedorahosted.org/389/ticket/47548
    
    Reviewed by: nhosoi(Thanks!)