power: supply: z2_battery: Drop unused variable

The kernel test robot reports an unused variable in the
Z2 battery code caused by a recent commit.

Fixes: a3b4388e ("power: supply: z2_battery: Convert to GPIO descriptors")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/z2_battery.c

@@ -90,9 +90,6 @@ static void z2_batt_ext_power_changed(struct power_supply *batt_ps)
 static void z2_batt_update(struct z2_charger *charger)
 {
 	int old_status = charger->bat_status;
-	struct z2_battery_info *info;
-
-	info = charger->info;
 
 	mutex_lock(&charger->work_lock);