ACPI: Always report a sync event after a lid state change

Currently not always an EV_SYN event is reported to userland
after the EV_SW SW_LID event has been sent. This is easy to verify
by using “input-events” from input-utils and just closing and opening
the lid.

Signed-off-by: Guillem Jover <guillem.jover@nokia.com>
Signed-off-by: Len Brown <len.brown@intel.com>