power: supply: core: introduce power_supply_has_property()

power: supply: core: introduce power_supply_has_property()

Introduce a helper to check if a power supply implements a certain
property. It will be used by the sysfs and hwmon code to remove similar
open-coded checks.
It also paves the way for the extension API to hook into.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20241111-power-supply-extensions-v4-3-7240144daa8e@weissschuh.net
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>