setup: simplify SUBDIRS

[Christopher Faylor]

On Tue, Aug 10, 2010 at 01:57:56AM -0500, Yaakov (Cygwin/X) wrote:
>Right now, "make clean" (or the other *clean targets) does not clean in
>libgetopt++.  Unless there is something I'm not aware of, libgetopt++
>can be handled like any other SUBDIRS, so that all targets are passed
>down to it as well.  Patch attached.

Hmm.  I could have sworn that it used to clean in that subdirectory.
Please check in.

Thanks.

cgf