gpio/pca953x: Use handle_simple_irq instead of handle_edge_irq

Make pca953x driver use the simple irq handler since no hardware control
is necessary and the driver lacks an irq_ack function. handle_edge_irq()
calls chip->irq_ack() which crashes since this function does not exist.
Signed-off-by: Erik Botö <erik.boto@pelagicore.com>
Signed-off-by: Richard Röjfors <richard.rojfors@pelagicore.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/gpio/pca953x.c

@@ -397,7 +397,7 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
 
 			irq_set_chip_data(irq, chip);
 			irq_set_chip_and_handler(irq, &pca953x_irq_chip,
-						 handle_edge_irq);
+						 handle_simple_irq);
 #ifdef CONFIG_ARM
 			set_irq_flags(irq, IRQF_VALID);
 #else