ARM: dts: sun8i: Add pmic nodes to sun8i-a23-gt90h-v4

Add nodes for the axp223 pmic and its regulators as found on
a23-gt90h-v4 tablets.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>