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: NNeilBrown <neilb@suse.de>
Acked-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

drivers/mfd/twl4030-irq.c

@@ -757,6 +757,7 @@ int twl4030_init_irq(struct device *dev, int irq_num)
 		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: