mfd: Set twl4030-irq tertiary interrupts to be nested/threaded.

As tertiary interrupts are handled by handle_twl4030_sih calling
handle_nested_irq, they do not need their own separate irq thread.
So mark them as 'nested_thread' interrupts to avoid the extra thread
creation.

Tested on GTA04 Pheonux.
Signed-off-by: NeilBrown <neilb@suse.de>
Tested-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/twl4030-irq.c

@@ -667,6 +667,7 @@ int twl4030_sih_setup(int module)
 		irq_set_chip_data(irq, agent);
 		irq_set_chip_and_handler(irq, &twl4030_sih_irq_chip,
 					 handle_edge_irq);
+		irq_set_nested_thread(irq, 1);
 		activate_irq(irq);
 	}