power: supply: max17042_battery: Refactor max17042_external_power_changed()

max17042_external_power_changed() is a wrapper around
"power_supply_changed(psy);" and it has the same prototype.

Remove it, replacing it with making the external_power_changed
callback directly point to power_supply_changed.

Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Cc: Purism Kernel Team <kernel@puri.sm>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/max17042_battery.c

@@ -499,11 +499,6 @@ static int max17042_property_is_writeable(struct power_supply *psy,
 	return ret;
 }
 
-static void max17042_external_power_changed(struct power_supply *psy)
-{
-	power_supply_changed(psy);
-}
-
 static int max17042_write_verify_reg(struct regmap *map, u8 reg, u32 value)
 {
 	int retries = 8;
@@ -1016,7 +1011,7 @@ static const struct power_supply_desc max17042_psy_desc = {
 	.get_property	= max17042_get_property,
 	.set_property	= max17042_set_property,
 	.property_is_writeable	= max17042_property_is_writeable,
-	.external_power_changed	= max17042_external_power_changed,
+	.external_power_changed	= power_supply_changed,
 	.properties	= max17042_battery_props,
 	.num_properties	= ARRAY_SIZE(max17042_battery_props),
 };