fix typo

Author: chx

reference/pcre/pattern.syntax.xml

@@ -1320,7 +1320,7 @@
    matches as if it were a capture group called <literal>MARK</literal> so it
    can be read from the <parameter>matches</parameter> of
    <function>preg_match</function> and will be passed to the
-   <parameter>callback</parameter> of <function>preg_match_all</function> etc.
+   <parameter>callback</parameter> of <function>preg_replace_callback</function> etc.
   </para>
  </section>