platform/x86: intel_int0002_vgpio: Use device_init_wakeup

Use device_init_wakeup and pm_wakeup_hard_event instead of directly
calling pm_system_wakeup(). This is the preferred way to do this and
this will allow the user to disable wakeup through INT0002 events
through sysfs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>