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.
Signed-off-by: Rob Crittenden <email@example.com>