HPCC-15765 Document LIKELY/ UNLIKELY

Signed-off-by: Jim DeFabia <jamesdefabia@lexisnexis.com>

docs/ECLLanguageReference/ECLR_mods/ResrvdKywds-LIKELY.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
 "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
-<sect1 id="ISVALID">
+<sect1 id="likely">
   <title>LIKELY and UNLIKELY</title>
 
   <para><emphasis role="bold">[</emphasis><emphasis>attrname</emphasis>