meson: don't put a symlink pointing to '20-systemd-ssh-proxy.conf' in /etc in all cases

On distros like SUSE where ssh config dropins in /usr are supported, there's no
need for a symlink in /etc/ssh/ssh_config.d/ that points to the dropin
installed somewhere in /usr (that is not reachable by ssh).

meson.build

@@ -204,6 +204,7 @@ sshconfdir = get_option('sshconfdir')
 if sshconfdir == ''
         sshconfdir = sysconfdir / 'ssh/ssh_config.d'
 endif
+conf.set10('LINK_SSH_PROXY_DROPIN', sshconfdir != 'no' and not sshconfdir.startswith('/usr/'))
 
 sshdconfdir = get_option('sshdconfdir')
 if sshdconfdir == ''

src/ssh-generator/meson.build

@@ -18,10 +18,12 @@ if conf.get('ENABLE_SSH_PROXY_CONFIG') == 1
                 output : '20-systemd-ssh-proxy.conf',
                 command : [jinja2_cmdline, '@INPUT@', '@OUTPUT@'],
                 install : true,
-                install_dir : libexecdir / 'ssh_config.d')
+                install_dir : sshconfdir.startswith('/usr/') ? sshconfdir : libexecdir / 'ssh_config.d')
 
-        install_emptydir(sshconfdir)
+        if not sshconfdir.startswith('/usr/')
+                install_emptydir(sshconfdir)
 
-        meson.add_install_script(sh, '-c',
-                ln_s.format(libexecdir / 'ssh_config.d' / '20-systemd-ssh-proxy.conf', sshconfdir / '20-systemd-ssh-proxy.conf'))
+                meson.add_install_script(sh, '-c',
+                        ln_s.format(libexecdir / 'ssh_config.d' / '20-systemd-ssh-proxy.conf', sshconfdir / '20-systemd-ssh-proxy.conf'))
+        endif
 endif

tmpfiles.d/20-systemd-ssh-generator.conf.in

@@ -7,7 +7,9 @@
 
 # See tmpfiles.d(5) for details
 
+{% if LINK_SSH_PROXY_DROPIN %}
 L {{SSHCONFDIR}}/20-systemd-ssh-proxy.conf - - - - {{LIBEXECDIR}}/ssh_config.d/20-systemd-ssh-proxy.conf
+{% endif %}
 {% if CREATE_SSHDPRIVSEPDIR %}
 d {{SSHDPRIVSEPDIR}} 0755
 {% endif %}