dt-bindings: phy: rockchip: add PCIe v3 phy

Add a new binding file for Rockchip PCIe v3 phy driver.

Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220825193836.54262-2-linux@fw-web.de


Signed-off-by: Vinod Koul <vkoul@kernel.org>