Fix for XFree86

[Suhaib M. Siddiqi]

> 
> I agree that the libX11.dll isn't needed for someone building the installation,
> but the dll and libraries should be offered as a separate tarball for the lazy.
>  It could be that someone would contribute X11 packages without the desire to
> build X11 itself.  If the dll and libraries weren't available then the
> contribution would be lost.

Ditto!!! :-)

I was asked by 3 Cygwin users personally for X11R6.3 development libraries for Cygwin B20.1.
Those 3 users do not care about XFree server, but would like to use X11R6.3 for developing
X11 apps for Cygwin on Win32.  That's another reason I put the precompiled libraries on the
download site.

--Suhaib