dt-bindings: media: Document bindings for HDMI RX Controller

Document bindings for the Synopsys DesignWare HDMI RX Controller.

Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Shreeya Patel <shreeya.patel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240719124032.26852-3-shreeya.patel@collabora.com


Signed-off-by: Sebastian Reichel <sre@kernel.org>