mfd: arizona: Use handle_simple_irq for IRQ dispatch chip

We use a dummy IRQ chip to dispatch interrupts to the two seperate IRQ
domains on the Arizona devices. This is just a simple software IRQ chip
and thus the current handle_edge_irq is unnecessary for its needs.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/arizona-irq.c b/drivers/mfd/arizona-irq.c
index 5e2f450..3a3fe7c 100644
--- a/drivers/mfd/arizona-irq.c
+++ b/drivers/mfd/arizona-irq.c
@@ -172,7 +172,7 @@
 	struct regmap_irq_chip_data *data = h->host_data;
 
 	irq_set_chip_data(virq, data);
-	irq_set_chip_and_handler(virq, &arizona_irq_chip, handle_edge_irq);
+	irq_set_chip_and_handler(virq, &arizona_irq_chip, handle_simple_irq);
 	irq_set_nested_thread(virq, 1);
 
 	/* ARM needs us to explicitly flag the IRQ as valid