dt-bindings: net: rockchip-dwmac: add rk3588 gmac compatible

Add compatible string for RK3588 gmac, which is similar to the RK3568
one, but needs another syscon device for clock selection.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Documentation/devicetree/bindings/net/rockchip-dwmac.yaml

@@ -25,6 +25,7 @@ select:
           - rockchip,rk3368-gmac
           - rockchip,rk3399-gmac
           - rockchip,rk3568-gmac
+          - rockchip,rk3588-gmac
           - rockchip,rv1108-gmac
   required:
     - compatible
@@ -45,11 +46,13 @@ properties:
               - rockchip,rk3328-gmac
               - rockchip,rk3366-gmac
               - rockchip,rk3368-gmac
+              - rockchip,rk3588-gmac
               - rockchip,rk3399-gmac
               - rockchip,rv1108-gmac
       - items:
           - enum:
               - rockchip,rk3568-gmac
+              - rockchip,rk3588-gmac
           - const: snps,dwmac-4.20a
 
   clocks:
@@ -81,6 +84,10 @@ properties:
     description: The phandle of the syscon node for the general register file.
     $ref: /schemas/types.yaml#/definitions/phandle
 
+  rockchip,php_grf:
+    description: The phandle of the syscon node for the peripheral general register file.
+    $ref: /schemas/types.yaml#/definitions/phandle
+
   tx_delay:
     description: Delay value for TXD timing. Range value is 0~0x7F, 0x30 as default.
     $ref: /schemas/types.yaml#/definitions/uint32