dt-bindings: display: ili9341: document canaan kd233's lcd

The Canaan KD233 development board has a built in LCD.
Add a specific compatible for it.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220705215213.1802496-3-mail@conchuod.ieSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Documentation/devicetree/bindings/display/panel/ilitek,ili9341.yaml

@@ -24,6 +24,7 @@ properties:
           - adafruit,yx240qv29
           # ili9341 240*320 Color on stm32f429-disco board
           - st,sf-tc240t-9370-t
+          - canaan,kd233-tft
       - const: ilitek,ili9341
 
   reg: true