Fix startup of the dirsrv@master Systemd unit on boot

The symlink created by Chef's service resource was wrong. Creating the
correct symlink fixes the automatic startup on boot

site-cookbooks/kosmos-dirsrv/resources/instance.rb

@@ -56,7 +56,14 @@ action :create do
   end
 
   service service_name do
-    action [:enable, :start]
+    action [:start]
+  end
+
+  # :enable on the dirsrv@master service creates the wrong file
+  # (/etc/systemd/system/dirsrv.target.wants/dirsrv@master.service), seems to
+  # be a Chef bug. Let's do it manually
+  link "/etc/systemd/system/multi-user.target.wants/dirsrv@master.service" do
+    to "/lib/systemd/system/dirsrv@.service"
   end
 
   cookbook_file "#{Chef::Config[:file_cache_path]}/users.ldif" do