Eradicate links and xrefs

These are all replaced by markdown ref links.

gobject/gvalue.c

@@ -35,9 +35,9 @@
  *     other type
  * @see_also: The fundamental types which all support #GValue
  *     operations and thus can be used as a type initializer for
- *     g_value_init() are defined by a separate interface.  See the <link
- *     linkend="gobject-Standard-Parameter-and-Value-Types">Standard
- *     Values API</link> for details.
+ *     g_value_init() are defined by a separate interface.  See the
+ *     [standard values API][gobject-Standard-Parameter-and-Value-Types]
+ *     for details
  * @title: Generic values
  *
  * The #GValue structure is basically a variable container that consists