dt-bindings: PCI: qcom: Add OPP table

PCIe needs to choose the appropriate performance state of RPMh power
domain based on the PCIe gen speed.

Adding the Operating Performance Points table allows to adjust power
domain performance state and ICC peak bw, depending on the PCIe data
rate and link width.

Link: https://lore.kernel.org/linux-pci/20240619-opp_support-v15-2-aa769a2173a3@quicinc.com
Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Author: Krishna chaitanya chundru

Documentation/devicetree/bindings/pci/qcom,pcie-sm8450.yaml

@@ -69,6 +69,10 @@ properties:
       - const: msi6
       - const: msi7
 
+  operating-points-v2: true
+  opp-table:
+    type: object
+
   resets:
     maxItems: 1