Avoids mistakes by making sure everyone allocates these the same
way.
The smart card code still has manual allocation because it has it's
own magical memory management.
A correct user initated disconnect sequence should send
a MCS Disconnect Provider Ultimatum PDU defined in T.128
upon a disconnect. This commit adds the implementation
the mentioned PDU and the actual write of the packet.
Signed-off-by: Henrik Andersson <hean01@cendio.com>