To abstract the way a platform reasons about which DTB is appropriate,
and the way it ultimately supplies the DTB image, introduce a new library
class to encapsulate this functionality.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>