arm64: dts: qcom: x1e78100-lenovo-thinkpad-t14s: add HDMI nodes

arm64: dts: qcom: x1e78100-lenovo-thinkpad-t14s: add HDMI nodes

The Thinkpad T14s embeds a transparent 4lanes DP->HDMI transceiver
connected to the third QMP Combo PHY 4 lanes.

Add all the data routing, disable mode switching and specify the
QMP Combo PHY should be in DP-Only mode to route the 4 lanes to
the underlying DP phy.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20251119-topic-x1e80100-hdmi-v7-3-2bee0e66cc1b@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>