dt-bindings: iommu: rockchip: Add Rockchip RK3588

Add a Rockchip RK3588 compatible

I split it from the vop2 patch series as suggested by Heiko[0]

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

[0]https://patchwork.kernel.org/project/dri-devel/patch/20231207080235.652719-1-andyshrk@163.com/

Link: https://lore.kernel.org/r/20231212005710.1837066-1-andyshrk@163.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: Andy Yan

Documentation/devicetree/bindings/iommu/rockchip,iommu.yaml

@@ -19,9 +19,14 @@ description: |+
 
 properties:
   compatible:
-    enum:
-      - rockchip,iommu
-      - rockchip,rk3568-iommu
+    oneOf:
+      - enum:
+          - rockchip,iommu
+          - rockchip,rk3568-iommu
+      - items:
+          - enum:
+              - rockchip,rk3588-iommu
+          - const: rockchip,rk3568-iommu
 
   reg:
     items: