fix 去除冗余转义 -- 到 -−

Author: ChenHuajun

postgresql/doc/src/sgml/func.sgml

@@ -29127,14 +29127,14 @@ SELECT xmltable.*
 CREATE TABLE xmlelements AS SELECT
 xml $$
   <root>
-   <element>  Hello<!-&minus; xyxxz -&minus;>2a2<?aaaaa?> <!-&minus;x-&minus;>  bbb<x>xxx</x>CC  </element>
+   <element>  Hello<!-- xyxxz -->2a2<?aaaaa?> <!--x-->  bbb<x>xxx</x>CC  </element>
   </root>
 $$ AS data;
 
 SELECT xmltable.*
   FROM xmlelements, XMLTABLE('/root' PASSING data COLUMNS element text);
          element
--&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-&minus;-
+-------------------------
    Hello2a2   bbbxxxCC
 ]]></screen>
     </para>