usb: dwc3: rtk: use scoped device node handling to simplify error paths

Obtain the device node reference with scoped/cleanup.h to reduce error
handling and make the code a bit simpler.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240814-b4-cleanup-h-of-node-put-usb-v1-9-95481b9682bc@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>