HID: thrustmaster: Fix memory leak in remove

thrustmaster_remove() does not release memory for
tm_wheel->change_request. This is fixed by the patch.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov <novikov@ispras.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>