dt-bindings: usb: genesys,gl850g: add downstream facing ports

In order to describe connections between Genesys GL850G hub and
corresponding Type-C connectors, follow example of RTS5411 and describe
downstream facing ports. Unline normal case of ports being connected to
a USB device, hotplug ports use OF graph representation.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: "Rob Herring (Arm)" <robh@kernel.org>
Link: https://lore.kernel.org/r/20250608-genesys-ports-v1-2-09ca19f6838e@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/usb/genesys,gl850g.yaml

@@ -28,6 +28,18 @@ properties:
 
   peer-hub: true
 
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    patternProperties:
+      '^port@':
+        $ref: /schemas/graph.yaml#/properties/port
+
+        properties:
+          reg:
+            minimum: 1
+            maximum: 4
+
 required:
   - compatible
   - reg