dt-bindings: usb: rt1711h: Add connector bindings

Add connector binding documentation for Richtek RT1711H Type-C
chip driver

It was noted by Rob Herring that the rt1711h binding docs
doesn't include the connector binding.

Thus this patch adds such documentation following the details
in Documentation/devicetree/bindings/usb/typec-tcpci.txt

Cc: Greg Kroah-Hartman <[e-mail]>
Cc: Rob Herring <[e-mail]>
Cc: Mark Rutland <[e-mail]>
CC: ShuFan Lee <[e-mail]>
Cc: Heikki Krogerus <[e-mail]>
Cc: Suzuki K Poulose <[e-mail]>
Cc: Chunfeng Yun <[e-mail]>
Cc: Yu Chen <[e-mail]>
Cc: Felipe Balbi <[e-mail]>
Cc: Hans de Goede <[e-mail]>
Cc: Andy Shevchenko <[e-mail]>
Cc: Jun Li <[e-mail]>
Cc: Valentin Schneider <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Reviewed-by: Rob Herring <[e-mail]>
Signed-off-by: John Stultz <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/devicetree/bindings/usb/richtek,rt1711h.txt

···
  - interrupts : <a b> where a is the interrupt number and b represents an
    encoding of the sense and level information for the interrupt.
 
+Required sub-node:
+- connector: The "usb-c-connector" attached to the tcpci chip, the bindings
+  of connector node are specified in
+  Documentation/devicetree/bindings/connector/usb-connector.txt
+
 Example :
 rt1711h@4e {
 	compatible = "richtek,rt1711h";
 	reg = <0x4e>;
 	interrupt-parent = <&gpio26>;
 	interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
+
+	usb_con: connector {
+		compatible = "usb-c-connector";
+		label = "USB-C";
+		data-role = "dual";
+		power-role = "dual";
+		try-power-role = "sink";
+		source-pdos = <PDO_FIXED(5000, 2000, PDO_FIXED_USB_COMM)>;
+		sink-pdos = <PDO_FIXED(5000, 2000, PDO_FIXED_USB_COMM)
+			     PDO_VAR(5000, 12000, 2000)>;
+		op-sink-microwatt = <10000000>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@1 {
+				reg = <1>;
+				usb_con_ss: endpoint {
+					remote-endpoint = <&usb3_data_ss>;
+				};
+			};
+		};
+	};
 };