mfd: enable wakeup on twl4030 IRQ.

Most of the interrupts that come through this line should trigger
wakeups:
  power button
  RTC alarm
  power available
  usb plug/unplug

so mark the interrupt as a wakeup interrupt.
This is particularly important for when the interrupt arrives during
the late suspend phase.  Without this setting it will be ignored.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
index 5d656e8..ad733d7 100644
--- a/drivers/mfd/twl4030-irq.c
+++ b/drivers/mfd/twl4030-irq.c
@@ -757,6 +757,7 @@
 		dev_err(dev, "could not claim irq%d: %d\n", irq_num, status);
 		goto fail_rqirq;
 	}
+	enable_irq_wake(irq_num);
 
 	return irq_base;
 fail_rqirq: