arm64: dts: qcom: sc8280xp-x13s: Use the correct DP PHY compatible

The DP PHY needs different settings when an eDP display is used.
Make sure these apply on the X13s.

FWIW
I could not notice any user-facing change stemming from this commit.

Fixes: f48c70b1 ("arm64: dts: qcom: sc8280xp-x13s: enable eDP display")
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230929-topic-x13s_edpphy-v1-1-ce59f9eb4226@linaro.orgSigned-off-by: Bjorn Andersson <andersson@kernel.org>

arch/arm64/boot/dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts

@@ -601,6 +601,7 @@ mdss0_dp3_out: endpoint {
 };
 
 &mdss0_dp3_phy {
+	compatible = "qcom,sc8280xp-edp-phy";
 	vdda-phy-supply = <&vreg_l6b>;
 	vdda-pll-supply = <&vreg_l3b>;