Input: gpio_keys - irq handling cleanup

Cleanup IRQ handling in gpio_keys:  bail after handling the IRQ, and
report IRQ_NONE if we never handle it.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/keyboard/gpio_keys.c

@@ -43,10 +43,11 @@ static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
 
 			input_event(input, type, button->code, !!state);
 			input_sync(input);
+			return IRQ_HANDLED;
 		}
 	}
 
-	return IRQ_HANDLED;
+	return IRQ_NONE;
 }
 
 static int __devinit gpio_keys_probe(struct platform_device *pdev)