No message=<ca ident> from GetCACaps, GetCACert, drop GetCACertChain
    
    In the SCEP Gutmann 10 spec there are no message=<ca ident> defined
    for the GetCACaps or GetCACert commands. The nourse 23 spec still
    defines this but it is optional. Don't send it at all.
    
    GetCACertChain doesn't exist at all in gutmann and was dropped in
    revision 19 by nourse.
    
    https://pagure.io/certmonger/issue/103
    
    Signed-off-by: Rob Crittenden <rcritten@redhat.com>