DOC: remove extra link to encoding descriptions

Author: Liudmila Mantrova

doc/src/sgml/charset.sgml

@@ -589,8 +589,7 @@ SELECT * FROM test1 ORDER BY a || b COLLATE "fr_FR";
      operating system. For example, <literal>"ru-RU"</literal> or
      <literal>"en-US"</literal>. Specifying the encoding with these
      options is not allowed either. If required, you can specify the
-     UTF8 encoding using the <literal>--encoding</literal> option. For details on
-     the supported encodings, see <xref linkend="multibyte-charset-supported">.
+     UTF8 encoding using the <literal>--encoding</literal> option.
     </para>
    </important>