power: supply: max17042_battery: Add support for the TECHNOLOGY attribute

The max17042 is intended for Li-Ion or Li-Po batteries, add a TECHNOLOGY
attribute to reflect this. Note this is hardcoded to Li-Ion as there is
no way to tell the difference, and Lithium-Ion Polymer batteries are
a sub-family of Lithium-Ion so Li-Ion technically is correct for both.

Using Li-Ion for both is already done by many drivers and is much
better then not providing any technology info at all.
Suggested-by: Wolfgang Wiedmeyer <wolfgit@wiedmeyer.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

drivers/power/supply/max17042_battery.c

@@ -78,6 +78,7 @@ struct max17042_chip {
 static enum power_supply_property max17042_battery_props[] = {
 	POWER_SUPPLY_PROP_STATUS,
 	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
 	POWER_SUPPLY_PROP_CYCLE_COUNT,
 	POWER_SUPPLY_PROP_VOLTAGE_MAX,
 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
@@ -238,6 +239,9 @@ static int max17042_get_property(struct power_supply *psy,
 		else
 			val->intval = 1;
 		break;
+	case POWER_SUPPLY_PROP_TECHNOLOGY:
+		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+		break;
 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
 		ret = regmap_read(map, MAX17042_Cycles, &data);
 		if (ret < 0)