Add some autoconf warnings

[Alexandre Julliard]

Francois Gouget <fgouget at free.fr> writes:

> Maybe a check that there is at least one functional sound system would
> be ok?
> 
> if test "$ac_cv_c_opensoundsystem" = "no" -a -z "$ALSALIBS" -a \
>          -z "$ARTSC_LIBS" -a -z "$NASLIBS" -a -z "$AUDIOIOLIBS"
> then
>      echo "*** No sound system was found. Windows applications will be silent."
> fi

Yes, something like that would be acceptable. 

-- 
Alexandre Julliard
julliard at winehq.org