add license information to images pkgs.
Fix a crash of racket on OpenBSD systems, when pixman is compiled with SSE support and racket tries to load cairo using libffi.

Bug found initially by Juan Francisco Cantero Hurtado. Reported by many.

Mark Kettenis (from the OpenBSD Project) found the real reason of the
crash and created this patch for libffi. Patch taken from OpenBSD Ports.