dt-bindings: display: anx7814: Add definition for anx7816

As requested by Robert Foss <rfoss@kernel.org>, this patch adds
definition for anx7816. It supplements the patch submitted to dri-devel.
Signed-off-by: Alicja Michalska <ahplka19@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/ZQjFabKW7QvrvsnG@tora

Documentation/devicetree/bindings/display/bridge/analogix,anx7814.yaml

@@ -17,6 +17,7 @@ properties:
       - analogix,anx7808
       - analogix,anx7812
       - analogix,anx7814
+      - analogix,anx7816
       - analogix,anx7818
 
   reg: