dt-bindings: arm: rockchip: Add BigTreeTech CB2 and Pi2

BigTreeTech CB2 and Pi2 are Rockchip RK3566 based boards

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Ivan Sergeev <ivan8215145640@gmail.com>
Link: https://lore.kernel.org/r/20250106-bigtreetech-cb2-v7-1-565567e2c0a4@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Documentation/devicetree/bindings/arm/rockchip.yaml

@@ -81,6 +81,17 @@ properties:
           - const: azw,beelink-a1
           - const: rockchip,rk3328
 
+      - description: BigTreeTech CB2 Manta M4/8P
+        items:
+          - const: bigtreetech,cb2-manta
+          - const: bigtreetech,cb2
+          - const: rockchip,rk3566
+
+      - description: BigTreeTech Pi 2
+        items:
+          - const: bigtreetech,pi2
+          - const: rockchip,rk3566
+
       - description: bq Curie 2 tablet
         items:
           - const: mundoreader,bq-curie2