The online LIST interrupt message is a NOP, but it's expected to not
have a reply (the server doesn't send one if it receives it before the
LIST finishes).
However, if the interrupt message arrives after the LIST finished, then
it does get a reply, and this causes the client to get out of step with
the server.
Fixes include:
1) flavor the interrupt NOP to make sure it never gets a reply,
2) introduce a new kadm_list_interrtupt message that is like a NOP that
produces no reply
3) always consume -after the LIST ends- a reply to any list interrupt
NOP on the client side.
This implements (1).
6b45c3512e