mfd: gateworks-gsc: Fix interrupt type

The Gateworks System Controller has an active-low interrupt.
Fix the interrupt request type.

Cc: <stable@vger.kernel.org>
Fixes: d8523499 ("mfd: Add Gateworks System Controller core driver")
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/gateworks-gsc.c

@@ -234,7 +234,7 @@ static int gsc_probe(struct i2c_client *client)
 
 	ret = devm_regmap_add_irq_chip(dev, gsc->regmap, client->irq,
 				       IRQF_ONESHOT | IRQF_SHARED |
-				       IRQF_TRIGGER_FALLING, 0,
+				       IRQF_TRIGGER_LOW, 0,
 				       &gsc_irq_chip, &irq_data);
 	if (ret)
 		return ret;