Input: gpio-keys - use IRQF_SHARED

There is nothing that disallows gpio-keys to share it's IRQ line
w/ other drivers. Make it use IRQF_SHARED in request_irq().

An example of other driver with which I'd like to share IRQ line
for GPIO buttons is ledtrig-gpio.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/keyboard/gpio_keys.c

@@ -147,6 +147,7 @@ static int __devinit gpio_keys_probe(struct platform_device *pdev)
 		}
 
 		error = request_irq(irq, gpio_keys_isr,
+				    IRQF_SHARED |
 				    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 				    button->desc ? button->desc : "gpio_keys",
 				    bdata);