ext/directfb/dfbvideosink.c: Lower rank from SECONDARY to MARGINAL. Plugins in -bad that might be autoplugged shouldn...

Original commit message from CVS:
* ext/directfb/dfbvideosink.c: (plugin_init):
Lower rank from SECONDARY to MARGINAL. Plugins in -bad that might
be autoplugged shouldn't trump plugins in -base, -good or -ugly
(in this case ximagesink).
* sys/glsink/glimagesink.c: (plugin_init):
Set rank to NONE to prevent it from being autoplugged until
errors are handled properly (see #357212).