dt-bindings: display: bridge: icn6211: Document DSI data-lanes property

It is necessary to specify the number of connected/used DSI data lanes when
using the DSI input port of this bridge. Document the 'data-lanes' property
of the DSI input port.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: devicetree@vger.kernel.org
To: dri-devel@lists.freedesktop.org
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407185617.179573-1-marex@denx.de

Documentation/devicetree/bindings/display/bridge/chipone,icn6211.yaml

@@ -41,10 +41,26 @@ properties:
 
     properties:
       port@0:
-        $ref: /schemas/graph.yaml#/properties/port
+        $ref: /schemas/graph.yaml#/$defs/port-base
+        unevaluatedProperties: false
         description:
           Video port for MIPI DSI input
 
+        properties:
+          endpoint:
+            $ref: /schemas/media/video-interfaces.yaml#
+            unevaluatedProperties: false
+
+            properties:
+              data-lanes:
+                description: array of physical DSI data lane indexes.
+                minItems: 1
+                items:
+                  - const: 1
+                  - const: 2
+                  - const: 3
+                  - const: 4
+
       port@1:
         $ref: /schemas/graph.yaml#/properties/port
         description: