arm64: dts: qcom: msm8992: Add PSCI support.

This SoC's firmware does not fully support the PSCI
spec, but it's good enough to bring the cores up.
Signed-off-by: Konrad Dybcio <konradybcio@gmail.com>
Link: https://lore.kernel.org/r/20200625182118.131476-11-konradybcio@gmail.comSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

arch/arm64/boot/dts/qcom/msm8992.dtsi

@@ -135,6 +135,11 @@ pmu {
 		interrupts = <GIC_PPI 7 (GIC_CPU_MASK_SIMPLE(4)| IRQ_TYPE_LEVEL_HIGH)>;
 	};
 
+	psci {
+		compatible = "arm,psci-0.2";
+		method = "hvc";
+	};
+
 	reserved-memory {
 		#address-cells = <2>;
 		#size-cells = <2>;