tmpfiles: split out config for systemd-resolve

This mirrors what was done in 564761fcae
for sysusers.d. If we allow separating resolved sysusers config
in a subpackage, we should do the same for the symlink that is
only useful when resolved is installed.

Related to #21317.

tmpfiles.d/etc.conf.in

@@ -12,9 +12,6 @@ L+ /etc/mtab - - - - ../proc/self/mounts
 {% if HAVE_SMACK_RUN_LABEL %}
 t /etc/mtab - - - - security.SMACK64=_
 {% endif %}
-{% if ENABLE_RESOLVE %}
-L! /etc/resolv.conf - - - - ../run/systemd/resolve/stub-resolv.conf
-{% endif %}
 C! /etc/nsswitch.conf - - - -
 {% if HAVE_PAM %}
 C! /etc/pam.d - - - -

tmpfiles.d/meson.build

@@ -7,6 +7,7 @@ files = [['README',               ''],
          ['journal-nocow.conf',   ''],
          ['systemd-nologin.conf', 'HAVE_PAM'],
          ['systemd-nspawn.conf',  'ENABLE_MACHINED'],
+         ['systemd-resolve.conf', 'ENABLE_RESOLVE'],
          ['systemd-tmp.conf',     ''],
          ['portables.conf',       'ENABLE_PORTABLED'],
          ['systemd-pstore.conf',  'ENABLE_PSTORE'],

tmpfiles.d/systemd-resolve.conf

@@ -0,0 +1,10 @@
+#  This file is part of systemd.
+#
+#  systemd is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU Lesser General Public License as published by
+#  the Free Software Foundation; either version 2.1 of the License, or
+#  (at your option) any later version.
+
+# See tmpfiles.d(5) for details
+
+L! /etc/resolv.conf - - - - ../run/systemd/resolve/stub-resolv.conf