dt-bindings: PCI: qcom: Allow 'vddpe-3v3-supply' again

dt-bindings: PCI: qcom: Allow 'vddpe-3v3-supply' again

Commit 756485bfbb85 ("dt-bindings: PCI: qcom,pcie-sc7280: Move SC7280 to
dedicated schema") incorrectly removed 'vddpe-3v3-supply' from the
bindings, which results in DT checker warnings like:

  arch/arm64/boot/dts/qcom/msm8996-sony-xperia-tone-dora.dtb: pcie@600000: Unevaluated properties are not allowed ('vddpe-3v3-supply' was unexpected)
  from schema $id: http://devicetree.org/schemas/pci/qcom,pcie.yaml#

Note that this property has been part of the Qualcomm PCIe bindings since
2018 and would need to be deprecated rather than simply removed if there is
a desire to replace it with 'vpcie3v3' which is used for some non-Qualcomm
controllers.

Link: https://lore.kernel.org/lkml/Zp_LPixNnh-2Fy5N@hovoldconsulting.com/
Fixes: 756485bfbb85 ("dt-bindings: PCI: qcom,pcie-sc7280: Move SC7280 to dedicated schema")
Link: https://lore.kernel.org/r/20240723151328.684-1-johan+linaro@kernel.org
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>