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

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: f48c70b111b4 ("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.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>