KMS sink requires some DRM libraries, SDL sink requires some SDL
libraries.

Suggested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Eric Curtin <ecurtin@redhat.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>