power: supply: bq27xxx: After charger plug in/out wait 0.5s for things to stabilize

bq27xxx_external_power_changed() gets called when the charger is plugged
in or out. Rather then immediately scheduling an update wait 0.5 seconds
for things to stabilize, so that e.g. the (dis)charge current is stable
when bq27xxx_battery_update() runs.

Fixes: 740b755a ("bq27x00: Poll battery state")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/bq27xxx_battery.c

@@ -2099,8 +2099,8 @@ static void bq27xxx_external_power_changed(struct power_supply *psy)
 {
 	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
 
-	cancel_delayed_work_sync(&di->work);
-	schedule_delayed_work(&di->work, 0);
+	/* After charger plug in/out wait 0.5s for things to stabilize */
+	mod_delayed_work(system_wq, &di->work, HZ / 2);
 }
 
 int bq27xxx_battery_setup(struct bq27xxx_device_info *di)