media: dt-bindings: rockchip: Add RK3576 Video Decoder bindings

The video decoder in RK3576 (vdpu383) is described the same way as the
one in RK3588 (vdpu381). A new compatible is added as the driver
implementation will be different.

Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>