Make sure, that vtysh_cmd.c is deterministically generated.

--- a/vtysh/extract.pl.in	2017-03-10 13:55:06.000000000 +0100
+++ b/vtysh/extract.pl.in	2017-06-24 00:51:56.460000000 +0200
@@ -214,7 +214,7 @@
 }
 
 # Output DEFSH
-foreach (keys %live) {
+foreach (sort keys %live) {
     my ($proto);
     my ($key);
     $key = $live{$_};
@@ -229,7 +229,7 @@
 {
 EOF
 
-foreach (keys %odefun) {
+foreach (sort keys %odefun) {
     my ($node, $str) = (split (/,/));
     $cmd = $ocmd{$_};
     $cmd =~ s/_cmd/_cmd_vtysh/;
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<tr><td><span title='2022-04-14 14:48:20 +0200'>2022-04-14</span></td><td><a href='/guix/commit/nix/nix-daemon?id=5f74169e8e03e64a15499866c6a6de9f38d36f2d'>daemon: Support systemd-style socket activation.</a><span class='msg-avail'>...<span class='msg-tooltip'>* nix/nix-daemon/guix-daemon.cc (SD_LISTEN_FDS_START): New macro.
(systemd_activation_sockets): New function.
(main): Use it.  Remove obsolete 'printMsg' call.
* doc/guix.texi (Invoking guix-daemon): Document socket activation.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-04-03 22:08:33 +0200'>2021-04-03</span></td><td><a href='/guix/commit/nix/nix-daemon?id=222fff253c6c6a3d1def16ed90723d7f2c4f9b89'>daemon: Remove dead code.</a><span class='msg-avail'>...<span class='msg-tooltip'>Reported by Noisytoot on #guix.

* nix/nix-daemon/shared.hh (showManPage): Remove.
* nix/nix-daemon/nix-daemon.cc (printHelp, programId): Remove.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-03-17 12:03:23 +0100'>2021-03-17</span></td><td><a href='/guix/commit/nix/nix-daemon?id=bc3896db25c788c181c7bcd65754e7cd378e9d9f'>daemon: Correctly handle '--discover' with no value.</a><span class='msg-avail'>...<span class='msg-tooltip'>Previously, we'd get:

  $ guix-daemon --discover
  error: basic_string::_M_construct null not valid

* nix/nix-daemon/guix-daemon.cc (parse_opt): Change second argument to
'settings.set' to properly handle case where ARG is NULL.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-11-29 15:08:26 +0100'>2020-11-29</span></td><td><a href='/guix/commit/nix/nix-daemon?id=79f9dee3c4c0e6d21066f142116a537207ae7ba4'>Use substitute servers on the local network.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/scripts/discover.scm: New file.
* Makefile.am (MODULES): Add it.
* nix/nix-daemon/guix-daemon.cc (options): Add "discover" option,
(parse-opt): parse it,
(main): start "guix discover" process when the option is set.
* guix/scripts/substitute.scm (%local-substitute-urls): New variable,
(substitute-urls): add it.
* gnu/services/base.scm (&lt;guix-configuration&gt;): Add "discover?"
field,
(guix-shepherd-service): honor it.
* doc/guix.texi (Invoking guix-daemon): Document "discover" option,
(Base Services): ditto.
</span></span></td><td>Mathieu Othacehe</td></tr>