use build-dir mzscheme to run setup, which is needed in particular when DESTDIR is set
use build-dir mzscheme to run setup, which is needed in particular when DESTDIR is set

svn: r3904

mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket