dt-bindings: net: add STM32MP13 compatible in documentation for stm32

New STM32 SOC have 2 GMACs instances.
GMAC IP version is SNPS 4.20.
Signed-off-by: Christophe Roullier <christophe.roullier@foss.st.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Documentation/devicetree/bindings/net/stm32-dwmac.yaml

@@ -22,18 +22,17 @@ select:
         enum:
           - st,stm32-dwmac
           - st,stm32mp1-dwmac
+          - st,stm32mp13-dwmac
   required:
     - compatible
 
-allOf:
-  - $ref: snps,dwmac.yaml#
-
 properties:
   compatible:
     oneOf:
       - items:
           - enum:
               - st,stm32mp1-dwmac
+              - st,stm32mp13-dwmac
           - const: snps,dwmac-4.20a
       - items:
           - enum:
@@ -75,12 +74,15 @@ properties:
   st,syscon:
     $ref: /schemas/types.yaml#/definitions/phandle-array
     items:
-      - items:
+      - minItems: 2
+        items:
           - description: phandle to the syscon node which encompases the glue register
           - description: offset of the control register
+          - description: field to set mask in register
     description:
       Should be phandle/offset pair. The phandle to the syscon node which
-      encompases the glue register, and the offset of the control register
+      encompases the glue register, the offset of the control register and
+      the mask to set bitfield in control register
 
   st,ext-phyclk:
     description:
@@ -112,12 +114,39 @@ required:
 
 unevaluatedProperties: false
 
+allOf:
+  - $ref: snps,dwmac.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - st,stm32mp1-dwmac
+              - st,stm32-dwmac
+    then:
+      properties:
+        st,syscon:
+          items:
+            minItems: 2
+            maxItems: 2
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - st,stm32mp13-dwmac
+    then:
+      properties:
+        st,syscon:
+          items:
+            minItems: 3
+            maxItems: 3
+
 examples:
   - |
     #include <dt-bindings/interrupt-controller/arm-gic.h>
     #include <dt-bindings/clock/stm32mp1-clks.h>
-    #include <dt-bindings/reset/stm32mp1-resets.h>
-    #include <dt-bindings/mfd/stm32h7-rcc.h>
     //Example 1
      ethernet0: ethernet@5800a000 {
            compatible = "st,stm32mp1-dwmac", "snps,dwmac-4.20a";