Tiny doc/lispref/variables.texi update.

* doc/lispref/variables.texi (File Local Variables):
Update hack-local-variables `mode-only' return value.

doc/lispref/ChangeLog

+2011-05-26  Glenn Morris  <rgm@gnu.org>
+
+	* variables.texi (File Local Variables):
+	Update hack-local-variables `mode-only' return value.
+
 2011-05-19  Glenn Morris  <rgm@gnu.org>
 
 	* lists.texi (Sets And Lists): Mention cl provides union etc.

doc/lispref/variables.texi

@@ -1673,9 +1673,10 @@ turn.  It calls @code{before-hack-local-variables-hook} and
 variables, respectively.
 
 If the optional argument @var{mode-only} is non-@code{nil}, then all
-this function does is return @code{t} if the @w{@samp{-*-}} line or
-the local variables list specifies a mode and @code{nil} otherwise.
-It does not set the mode nor any other file-local variable.
+this function does is return a symbol specifying the major mode,
+if the @w{@samp{-*-}} line or the local variables list specifies one,
+and @code{nil} otherwise.  It does not set the mode nor any other
+file-local variable.
 @end defun
 
 @defvar file-local-variables-alist