arm64: dts: mediatek: mt8365: use a specific SCPSYS compatible

SoCs should use dedicated compatibles for each of their syscon nodes to
precisely describe the block.  Using an incorrect compatible does not
allow to properly match/validate children of the syscon device.  Replace
SYSCFG compatible, which does not have children, with a new dedicated
one for SCPSYS block.

Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Tested-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240612092421.52917-2-krzysztof.kozlowski@linaro.org


Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>