[PATCH] $thread convenience variable

[Eli Zaretskii]

> Date: Sun, 13 Jun 2010 18:31:33 -0700
> From: Stan Shebs <stan@codesourcery.com>
> 
> +                                                           See
> + @ref{Convenience Vars,, Convenience Variables},

This should be just @xref.

The patch for the manual is okay, with this change.