dt-bindings: PCI: rcar: Correct example to match reality

Correct the USB subnodes in the example, as in f7d569c ("ARM: dts:
r8a779x: Fix PCI bus dtc warnings").
  1. Drop the bogus 'device_type = "pci"' properties,
  2. Correct the unit addresses.

Update other bits in the example to match real use:
  1. Rename the USB subnodes from "pci" to "usb",
  2. Update the "phys" property.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/pci/pci-rcar-gen2.txt

@@ -60,17 +60,15 @@ Example SoC configuration:
 				 0x0800 0 0 1 &gic 0 108 IRQ_TYPE_LEVEL_HIGH
 				 0x1000 0 0 2 &gic 0 108 IRQ_TYPE_LEVEL_HIGH>;
 
-		pci@0,1 {
+		usb@1,0 {
 			reg = <0x800 0 0 0 0>;
-			device_type = "pci";
-			phys = <&usbphy 0 0>;
+			phys = <&usb0 0>;
 			phy-names = "usb";
 		};
 
-		pci@0,2 {
+		usb@2,0 {
 			reg = <0x1000 0 0 0 0>;
-			device_type = "pci";
-			phys = <&usbphy 0 0>;
+			phys = <&usb0 0>;
 			phy-names = "usb";
 		};
 	};