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>