arm64: dts: qcom: sc7280: Add ports subnodes in usb/dp qmpphy node

arm64: dts: qcom: sc7280: Add ports subnodes in usb/dp qmpphy node

Add the USB3+DP Combo QMP PHY port subnodes to facilitate the
description of the connection between the hardware blocks.

Put it in the SoC DTSI to avoid duplication in the device DTs.

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
Link: https://lore.kernel.org/r/20230929-sc7280-qmpphy-ports-v2-1-aae7e9c286b0@fairphone.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>