Fix readline for platforms without <wchar.h>

[Chet Ramey]

> [ Chet, I don't now if you ever received the change that was
>   origionally made to the copy of readline in the GDB tree.  Just in
>   case you intend to incorporate such a change in the next release of
>   readline, this patch solves a problem with it. ]
> 
> There is a problem with one of our local GDB fixes for readline:

I'm not going to include wcwidth in libreadline.  It's not appropriate
for libraries to be conditionally including C library functions -- it
just causes problems down the line.  That's what the calling
application should be doing. 

That said, your fix was better than changing the source, since I don't
see how wcwidth is going to work without wchar.h anyway. 

Chet

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
( ``Discere est Dolere'' -- chet )

Chet Ramey, ITS, CWRU    chet@po.CWRU.Edu    http://cnswww.cns.cwru.edu/~chet/