dt-bindings: phy: qcom,sc8280xp-qmp-pcie-phy: Document the X1E80100 QMP PCIe PHY Gen4 x4

The sixth PCIe instance on X1E80100 can be used in either 4-lane mode or
2-lane mode. Document the 4-lane mode as a separate compatible.

Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20240823-x1e80100-phy-add-gen4x4-v3-1-b7765631ca01@linaro.org


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