power: supply: hwmon: Add support for power sensors

Currently, more than seven power supply drivers are supporting
POWER_SUPPLY_PROP_POWER_NOW, but their power readings are not being
reported through the hwmon subsystem.

Fix this by adding support for power sensors to the power supply
hwmon integration.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20240528222115.791511-1-W_Armin@gmx.de


Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>