platform/chrome: chromeos_laptop - add SPDX identifier

Replace the original license statement with the SPDX identifier.
Add also one line of description as recommended by the COPYING file.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
1 file changed