idviews: Create Default Trust View for upgraded servers
    
    For upgraded servers with enabled AD trust support, we want to
    ensure that Default Trust View entry is created.
    
    Part of: https://fedorahosted.org/freeipa/ticket/3979
    
    Reviewed-By: Petr Viktorin <pviktori@redhat.com>
    Reviewed-By: Petr Vobornik <pvoborni@redhat.com>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>