dt-bindings: arm: sunxi: Add Xunlong OrangePi 4A board

The OrangePi 4A is a typical Raspberry Pi model B sized development
board from Xunlong designed around an Allwinner T527 SoC.

Add its compatible name to the list of valid ones.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20250628161608.3072968-2-wens@kernel.org
Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Author: wens

Documentation/devicetree/bindings/arm/sunxi.yaml

@@ -996,6 +996,11 @@ properties:
           - const: xunlong,orangepi-3
           - const: allwinner,sun50i-h6
 
+      - description: Xunlong OrangePi 4A
+        items:
+          - const: xunlong,orangepi-4a
+          - const: allwinner,sun55i-t527
+
       - description: Xunlong OrangePi Lite
         items:
           - const: xunlong,orangepi-lite