soc: boards: Add MediaTek MT8195 Audio DSP

This is a soc/board integration for the MediaTek Audio DSP device on
the MT8195 SOC, along with a Zephyr mtk_adsp soc integration that will
work to support similar 8186 and 8188 device shortly.

A python loader (similar to cavsload.py) is included that will run in
developer mode on current chromebooks (an HP x360 13b-ca000 was
tested) with an unmodified kernel.

Signed-off-by: Andy Ross <andyross@google.com>

dts/bindings/clock/mediatek,mt8195_cpuclk.yaml

@@ -0,0 +1,16 @@
+# Copyright 2023 The ChromiumOS Authors
+# SPDX-License-Identifier: Apache-2.0
+
+description: MediaTek Audio DSP CPU Frequency Control
+compatible: "mediatek,mt8195_cpuclk"
+properties:
+  freqs_mhz:
+    type: array
+    description: Available frequencies in ascending order
+    required: true
+  reg:
+    type: array
+  cg_reg:
+    type: int
+  pll_ctrl_reg:
+    type: int