Fix Barry's markup.

Doc/lib/libsunaudio.tex

@@ -50,7 +50,7 @@ are other references to it. A closed device should not be used again.
 \begin{methoddesc}[audio device]{fileno}{}
 Returns the file descriptor associated with the device.  This can be
 used to set up \code{SIGPOLL} notification, as described below.
-\end{methoddocs}
+\end{methoddesc}
 
 \begin{methoddesc}[audio device]{drain}{}
 This method waits until all pending output is processed and then returns.