usb: gadget: udc: renesas_usb3: Add bindings for r8a774c0

Document RZ/G2E (R8A774C0) SoC bindings.
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

Documentation/devicetree/bindings/usb/renesas_usb3.txt

@@ -3,6 +3,7 @@ Renesas Electronics USB3.0 Peripheral driver
 Required properties:
   - compatible: Must contain one of the following:
 	- "renesas,r8a774a1-usb3-peri"
+	- "renesas,r8a774c0-usb3-peri"
 	- "renesas,r8a7795-usb3-peri"
 	- "renesas,r8a7796-usb3-peri"
 	- "renesas,r8a77965-usb3-peri"