[multi-tty] server-process set to nil

[Juanma Barranquero]

The multi-tty's server.el has (among many others) this difference with
the HEAD one:

  ;; Now any previous server is properly stopped.
-  (unless leave-dead
+    (if leave-dead
+       (progn
+         (server-log (message "Server stopped"))
+         (setq server-process nil))
    (let* ((server-dir (if server-use-tcp server-auth-dir server-socket-dir))
           (server-file (expand-file-name server-name server-dir)))

Is there any reason to set server-process to nil? I find very
convenient the HEAD behavior of having the dead process still in
server-process (until a new server is created, of course), because I
attach properties to it when it is created and I use them at
kill-emacs-hook time.

            Juanma