dt-bindings: net: dsa: qca8k: improve port definition documentation

Clean and improve port definition for qca8k documentation by referencing
the dsa generic port definition and adding the additional specific port
definition.
Signed-off-by: NAnsuel Smith <ansuelsmth@gmail.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/dsa/qca8k.yaml

@@ -99,40 +99,9 @@ patternProperties:
         type: object
         description: Ethernet switch ports
 
-        properties:
-          reg:
-            description: Port number
-
-          label:
-            description:
-              Describes the label associated with this port, which will become
-              the netdev name
-            $ref: /schemas/types.yaml#/definitions/string
-
-          link:
-            description:
-              Should be a list of phandles to other switch's DSA port. This
-              port is used as the outgoing port towards the phandle ports. The
-              full routing information must be given, not just the one hop
-              routes to neighbouring switches
-            $ref: /schemas/types.yaml#/definitions/phandle-array
-
-          ethernet:
-            description:
-              Should be a phandle to a valid Ethernet device node.  This host
-              device is what the switch port is connected to
-            $ref: /schemas/types.yaml#/definitions/phandle
-
-          phy-handle: true
-
-          phy-mode: true
-
-          fixed-link: true
-
-          mac-address: true
-
-          sfp: true
+        $ref: dsa-port.yaml#
 
+        properties:
           qca,sgmii-rxclk-falling-edge:
             $ref: /schemas/types.yaml#/definitions/flag
             description:
@@ -154,10 +123,7 @@ patternProperties:
               SGMII on the QCA8337, it is advised to set this unless a communication
               issue is observed.
 
-        required:
-          - reg
-
-        additionalProperties: false
+        unevaluatedProperties: false
 
 oneOf:
   - required: