putty's telnet.c fix

From: dwalin (dwalin_at_dwalin.ru)
Date: 08/22/05 

Date: 22 Aug 2005 03:23:53 -0700

there's a bug in the most recent version (r5512) of telnet.c. while the
latest patch may have fixed something, i have a telnetd here that is
not compatible with it. this telnetd sends WONT for TELOPT_LIMEMODE
(34) and expects WONT back, otherwise hangs and disconnects after the
timeout.
here's a little patch to make it happy:

--- putty-0.58/telnet.c 2005-04-05 23:37:52.000000000 +0400
+++ putty/telnet.c 2005-08-22 14:09:39.000000000 +0400
@@ -398,7 +398,7 @@
      * a negative ack to indicate refusal. If the request was
      * negative (WONT / DONT), we must do nothing.
      */
- if (cmd == WILL || cmd == DO)
+ if (cmd == WILL || cmd == DO || cmd == WONT)
         send_opt(telnet, (cmd == WILL ? DONT : WONT), option);
 }

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