arm64: dts: mt8195: Add cpufreq node

Add cpufreq node for mt8195.

Signed-off-by: YT Lee <yt.lee@mediatek.corp-partner.google.com>
Signed-off-by: Tinghan Shen <tinghan.shen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220811025813.21492-11-tinghan.shen@mediatek.com


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>