docs: Fix docs to match reference to autosecondary

The docs had been wrong since the feature was renamed in
d3dfd71

Signed-off-by: Josh Soref <2119212+jsoref@users.noreply.github.com>

docs/settings.rst

@@ -1860,7 +1860,7 @@ and :doc:`Virtual Hosting <guides/virtual-instances>` how this can differ.
 -  Boolean
 -  Default: no
 
-Turn on supermaster support. See :ref:`autoprimary-operation`.
+Turn on autosecondary support. See :ref:`autoprimary-operation`.
 
 .. _setting-svc-autohints: