gpio: pch: Use for_each_set_bit() in IRQ handler

This simplifies and standardizes the AB IRQ handler by using
the for_each_set_bit() library function.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

drivers/gpio/gpio-pch.c

@@ -313,16 +313,14 @@ static void pch_irq_ack(struct irq_data *d)
 static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
 {
 	struct pch_gpio *chip = dev_id;
-	u32 reg_val = ioread32(&chip->reg->istatus);
+	unsigned long reg_val = ioread32(&chip->reg->istatus);
 	int i, ret = IRQ_NONE;
 
-	for (i = 0; i < gpio_pins[chip->ioh]; i++) {
-		if (reg_val & BIT(i)) {
-			dev_dbg(chip->dev, "%s:[%d]:irq=%d  status=0x%x\n",
-				__func__, i, irq, reg_val);
-			generic_handle_irq(chip->irq_base + i);
-			ret = IRQ_HANDLED;
-		}
+	for_each_set_bit(i, &reg_val, gpio_pins[chip->ioh]) {
+		dev_dbg(chip->dev, "%s:[%d]:irq=%d  status=0x%lx\n", __func__,
+			i, irq, reg_val);
+		generic_handle_irq(chip->irq_base + i);
+		ret = IRQ_HANDLED;
 	}
 	return ret;
 }