When a connection is reset while we still have an outstanding request,

When a connection is reset while we still have an outstanding request,
the connection from the request to the rest of the structure is removed,
so we don't send any old data over the new connection.

However, the old code dereferences axc at a couple of places before
we check it for NULL.

Found the hard way by Mischa Peters while stress testing agentx support
for vmd.

OK tb@, sthen@