fix msys w/ mingw64 (32/64) & cygwin without zlib builds
fix msys w/ mingw64 (32/64) & cygwin without zlib builds
DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf,DmitrySigaev/gpac-sf