do_tcpip_forward_request_exc): Moved handling of the failure case
to the exception handler.

* src/channel.c (do_channel_open): Use SSH_CHANNEL_MAX_PACKET_FUZZ
* src/server_session.c (make_server_session): Likewise.
* src/client.c (make_client_session): Likewise.
* src/tcpforward.c (make_tcpip_channel): Likewise

Rev: src/tcpforward.c:1.44