dt-bindings: PCI: qcom,pcie-sm8150: Merge SC8180x into SM8150

dt-bindings: PCI: qcom,pcie-sm8150: Merge SC8180x into SM8150

After the commit 26daa18e35eb ("dt-bindings: PCI: qcom,pcie-sc8180x:
Drop unrelated clocks from PCIe hosts") and the
commit e1cb67ab82aa ("dt-bindings: PCI: qcom,pcie-sm8150: Drop unrelated
clocks from PCIe hosts"), which dropped two clocks from each of the
bindings, the devices share entire binding and could be kept in one file
for simplicity.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20251217-dt-bindings-pci-qcom-v2-1-873721599754@oss.qualcomm.com