arm64: dts: qcom: msm8996-oneplus-common: drop vdda-supply from DSI PHY

14nm DSI PHY has the only supply, vcca. Drop the extra vdda-supply.

Fixes: 5a134c94 ("arm64: dts: qcom: msm8996: add support for oneplus3(t)")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230109042406.312047-1-dmitry.baryshkov@linaro.org