[BUG] fix double-decrement of server connections

If a client does a sudden dirty close (CL_STCLOSE) during a server
connect turn-around, then the number of server connections is
decremented twice. This causes huge problems on the affected
server because when its connection number becomes negative, it
overflows and prevents the server from accepting new connections
due to an apparent saturation.

The fix consists in not decrementing the counter if the server is
in a turn-around state.
1 file changed