Describe in each CPU node the regulator supplying it.

Fixes: 260c04d4 ("arm64: dts: mediatek: cherry: Enable MT6315 regulators on SPMI bus")
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240110142305.755367-2-nfraprado@collabora.comSigned-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>