power: supply: bq27xxx: fix sign of current_now for newer ICs

Commit cd060b4d ("power: supply: bq27xxx: fix polarity of current_now")
changed the sign of current_now for all bq27xxx variants, but on BQ28Z610
I'm now seeing negated values *with* that patch.

The GTA04/Openmoko device that was used for testing uses a BQ27000 or
BQ27010 IC, so I assume only the BQ27XXX_O_ZERO code path was incorrect.
Revert the behaviour for newer ICs.

Fixes: cd060b4d "power: supply: bq27xxx: fix polarity of current_now"
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/bq27xxx_battery.c

@@ -1827,7 +1827,7 @@ static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
 		val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
 	} else {
 		/* Other gauges return signed value */
-		val->intval = -(int)((s16)curr) * 1000;
+		val->intval = (int)((s16)curr) * 1000;
 	}
 
 	return 0;