extcon: gpio: Use power efficient workqueue for debounce

The debounce timeout is generally quite long and the work not performance
critical so allow the scheduler to run the work anywhere rather than in
the normal per-CPU workqueue.
Signed-off-by: NMark Brown <broonie@linaro.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NMyungjoo Ham <myungjoo.ham@samsung.com>

drivers/extcon/extcon-gpio.c

@@ -56,7 +56,7 @@ static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
 {
 	struct gpio_extcon_data *extcon_data = dev_id;
 
-	schedule_delayed_work(&extcon_data->work,
+	queue_delayed_work(system_power_efficient_wq, &extcon_data->work,
 			      extcon_data->debounce_jiffies);
 	return IRQ_HANDLED;
 }