arm64: dts: qcom: ipq6018: Add pcie support

ipq6018 has 1 pcie gen3 port. This patch adds the support for the same.

The GICv2m reg property value is a guess based on similar SoCs
description in downstream Codeaurora kernel. It appears to work.

Signed-off-by: Selvam Sathappan Periakaruppan <speriaka@codeaurora.org>
[baruch: adjust #address-cells/#size-cells; drop unsupported property;
 increase parf registers size]
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Link: https://lore.kernel.org/r/0f733656666fa6adaa8e196419ebcfd04677d173.1620203062.git.baruch@tkos.co.il


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>