vpnkit: remove the old port forwarding shutdown protocol

Before we multiplexed all port forwards over one connection, we had
to layer our own custom shutdown protocol on top to work around
Hyper-V socket bugs. This is not needed any more because the same
work is done within the multiplexing protocol.

Note this requires an updated vpnkit-forwarder.

Signed-off-by: David Scott <[email protected]>

Author: djs55

src/bin/connect.ml

@@ -45,7 +45,7 @@ module Hvsock = struct
   (* Avoid using `detach` because we don't want to exhaust the
      thread pool since this will block the main TCP/IP stack. *)
   module F =
-    Hvsock_lwt.Flow_shutdown.Make(Host.Time)
+    Hvsock_lwt.Flow.Make(Host.Time)
       (Hvsock_lwt.In_main_thread.Make(Host.Main))
       (Hvsock.Af_hyperv)