Configure bug

[Bruce Korb]

I accidentally created my build subdirectory as "SunOS-i86pc" instead
of "_SunOS-i86pc" and the consequence was a mess:

> $ cd SunOS-i86pc
> $ ../configure --prefix=$HOME --bindir=$HOME/$BINDIR \
>   --libdir=$HOME/$LIBDIR CC=$(which cc)
> ln: cannot create SunOS-i86pc/agen5/test/expr.test: No such file or directory
> ln: cannot create SunOS-i86pc/agen5/test/match.test: No such file or directory
> ln: cannot create SunOS-i86pc/agen5/test/reorder.test: No such file or 
> directory

With the underscore prefix, all was fine.

> $ autoconf --version
> autoconf (GNU Autoconf) 2.59
> Written by David J. MacKenzie and Akim Demaille.

Thanks -Bruce