spec: better variable name for operator example

Suggested by @yaxinlx.

Fixes #41612.

Change-Id: I98b9968a95d090ee3c67ff02678e1874e6d98c33
Reviewed-on: https://go-review.googlesource.com/c/go/+/257159
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

doc/go_spec.html

diff --git a/doc/go_spec.html b/doc/go_spec.html
index 154bdbf..e9e9e42 100644
--- a/doc/go_spec.html
+++ b/doc/go_spec.html
@@ -1,6 +1,6 @@
 <!--{
 	"Title": "The Go Programming Language Specification",
-	"Subtitle": "Version of Jan 14, 2020",
+	"Subtitle": "Version of Sep 24, 2020",
 	"Path": "/ref/spec"
 }-->
 
@@ -3646,7 +3646,7 @@
 x &lt;= f()
 ^a &gt;&gt; b
 f() || g()
-x == y+1 &amp;&amp; &lt;-chanPtr &gt; 0
+x == y+1 &amp;&amp; &lt;-chanInt &gt; 0
 </pre>