arm64: dts: mediatek: mt8188-geralt: Add little core CPU power supplies

arm64: dts: mediatek: mt8188-geralt: Add little core CPU power supplies

The device tree for the MT8188 Geralt is missing power supplies for all
the CPU cores. Power for the little cores is fed from the MT6359 PMIC.
Power for the big cores is fed from an MT6319 PMIC on SPMI. The latter
is currently not working in Linux.

Add the power supplies for the little cores.

Supplies for the big cores will be added once the issue with SPMI is
resolved.

Reviewed-by: Fei Shao <fshao@chromium.org>
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>