gpio: mcp23s08: request a shared interrupt

Request a shared interrupt when requesting a mcp23s08 GPIO interrupt.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-mcp23s08.c

@@ -485,7 +485,8 @@ static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
 		return -ENODEV;
 
 	err = devm_request_threaded_irq(chip->dev, mcp->irq, NULL, mcp23s08_irq,
-					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					IRQF_TRIGGER_LOW | IRQF_ONESHOT |
+					IRQF_SHARED,
 					dev_name(chip->dev), mcp);
 	if (err != 0) {
 		dev_err(chip->dev, "unable to request IRQ#%d: %d\n",