dt-bindings: PCI: qcom: Add oneOf to compatible match

Prepare for extending compatible list by adding oneOf keyword.  No
functional changes.

Link: https://lore.kernel.org/r/20230106081203.14118-1-krzysztof.kozlowski@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rob Herring <robh@kernel.org>