docs: Fix missing ref in the dnsdist docs

diff --git a/pdns/dnsdistdist/docs/rules-actions.rst b/pdns/dnsdistdist/docs/rules-actions.rst
index 4bf8b85b33c07bbfbdc72e9d564f42e39ed5bbcb..28850879699eccf01afdf6d24eb92b9b15c5b6bf 100644 (file)
--- a/pdns/dnsdistdist/docs/rules-actions.rst
+++ b/pdns/dnsdistdist/docs/rules-actions.rst
@@ -566,7 +566,7 @@ These ``DNSRule``\ s be one of the following items:
 .. function:: OpcodeRule(code)
 
   Matches queries with opcode ``code``.
-  ``code`` can be directly specified as an integer, or one of the `built-in DNSOpcodes <DNSOpcode>`.
+  ``code`` can be directly specified as an integer, or one of the :ref:`built-in DNSOpcodes <DNSOpcode>`.
 
   :param int code: The opcode to match