Add references the 'IYUV' mediatype wherever 'I420' is referenced, as
they are identical.
Signed-off-by: Connor McAdams <cmcadams@codeweavers.com>
Signed-off-by: Zebediah Figura <z.figura12@gmail.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>