arm64: dts: qcom: ipq6018: enable the GICv2m support

GIC used in the IPQ6018 SoCs has one instance of the GICv2m extension,
which supports upto 32 MSI interrupts. Lets add support for the same.

Signed-off-by: Kathiravan T <quic_kathirav@quicinc.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1644334525-11577-3-git-send-email-quic_kathirav@quicinc.com