Backport commit 07ea5ef99 from Emacs

* doc/org.texi (A Texinfo example): Fix reference style.

Fix reference style in org.texi
07ea5ef99a509622981a8ca69aadff15cbc0ef10
Martin Rudalics
Sun Oct 1 10:30:33 2017 +0200

<https://lists.gnu.org/archive/html/emacs-devel/2017-10/msg00019.html>

doc/org.texi

@@ -14031,7 +14031,7 @@ A somewhat obsessive function.
 @node A Texinfo example
 @subsection A Texinfo example
 
-Here is a more detailed example Org file.  @xref{GNU Sample
+Here is a more detailed example Org file.  See @ref{GNU Sample
 Texts,,,texinfo,GNU Texinfo Manual} for an equivalent example using Texinfo
 code.