eval.xml: add link to ParseError exception page (#3446)

reference/misc/functions/eval.xml

@@ -81,7 +81,7 @@
    <function>eval</function> returns &null; unless 
    <literal>return</literal> is called in the evaluated code, in which case
    the value passed to <literal>return</literal> is returned. As of PHP 7, if there is a
-   parse error in the evaluated code, <function>eval</function> throws a ParseError exception.
+   parse error in the evaluated code, <function>eval</function> throws a <classname>ParseError</classname> exception.
    Before PHP 7, in this case <function>eval</function> returned
    &false; and execution of the following code continued normally. It is
    not possible to catch a parse error in <function>eval</function>