extcon: axp288: Add wakeup support

On devices with an AXP288, we need to wakeup from suspend when a charger
is plugged in, so that we can do charger-type detection and so that the
axp288-charger driver, which listens for our extcon events, can configure
the input-current-limit accordingly.

Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>