Fix broken link

Author: jorund1

doc/howto/mod_auth_openidc_feide.rst

@@ -11,7 +11,7 @@ First check if the plugin is already installed and enabled::
     $ sudo apache2ctl -M | grep openid
       auth_openidc_module (shared)
 
-If it is, go straight to `Configuration`_.
+If it is, go straight to :ref:`openidc_feide_howto_configuration`.
 
 If not:
 
@@ -34,6 +34,8 @@ Disable with::
 
     $ sudo a2dismod auth_openidc
 
+
+.. _openidc_feide_howto_configuration:
 Feide Kundeportal configuration
 ===============================