arm64: dts: qcom: Add DTS for MSM8976 and MSM8956 SoCs

This commit adds device trees for MSM8956 and MSM8976 SoCs.
They are *almost* identical, with minor differences, such as
MSM8956 having two A72 cores less.

However, there is a bug in Sony Loire bootloader that requires presence
of all 8 cores in the cpu{} node, so these will not be deleted.
Co-developed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Co-developed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221111120156.48040-11-angelogioacchino.delregno@collabora.com

arch/arm64/boot/dts/qcom/msm8956.dtsi

+// SPDX-License-Identifier: BSD-3-Clause
+/*
+ * Copyright (c) 2016-2022, AngeloGioacchino Del Regno
+ *                          <angelogioacchino.delregno@collabora.com>
+ * Copyright (c) 2022, Konrad Dybcio <konrad.dybcio@somainline.org>
+ * Copyright (c) 2022, Marijn Suijten <marijn.suijten@somainline.org>
+ */
+
+#include "msm8976.dtsi"
+
+&pmu {
+	interrupts = <GIC_PPI 7 (GIC_CPU_MASK_SIMPLE(6) | IRQ_TYPE_LEVEL_HIGH)>;
+};
+
+/*
+ * You might be wondering.. why is it so empty out there?
+ * Well, the SoCs are almost identical.
+ */