arm64: dts: mediatek: mt6795-xperia-m5: Add MT6331 Combo PMIC

arm64: dts: mediatek: mt6795-xperia-m5: Add MT6331 Combo PMIC

This smartphone uses the Helio X10 standard MT6331+MT6332 combo PMICs:
include the mt6331 devicetree and add the required interrupt.

Note that despite there being two interrupts, one for MT6331 and one
for MT6332, in configurations using the companion PMIC, the interrupt
of the latter fires for both events on MT6331 and for ones on MT6332,
while the interrupt for the main PMIC fires only for events of the
main PMIC.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230412112739.160376-25-angelogioacchino.delregno@collabora.com
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>