dt-bindings: display: bridge: Reject additional properties in ports node

Document the #address-cells and #size-cells properties of the ports node
in the schemas of the bridge DT bindings, and set additionalProperties
to false to reject additional properties.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>