arm64: dts: qcom: x1e80100-*: Drop useless DP3 compatible override

arm64: dts: qcom: x1e80100-*: Drop useless DP3 compatible override

Back when display support was added initially to CRD, and we used to have
two separate compatibles for eDP and DP, it was supposed to override the
DP compatible with the eDP one in the board specific devicetree. Since
then, the DP driver has been reworked to figure out the eDP/DP at runtime
while only DP compatible remained in the end.

Even though the override does nothing basically, drop it to avoid
further confusion. Drop it from all X Elite based platforms.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250509-x1e80100-dts-drop-useless-dp-compatible-override-v2-1-126db05cb70a@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>