Input: atkbd - correct MSC_SCAN events for force_release keys

Without the change either no scancode would be reported on release of
force_release keys, or - if the key is marked as force_release erroneously
- the release event and the scancode would be reported in separate reports
to the input layer.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>