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 <[e-mail]>
Acked-by: Kevin Hilman <[e-mail]>
Signed-off-by: Samuel Ortiz <[e-mail]>

drivers/mfd/twl4030-irq.c

···
 		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: