Use SPDX 3.0 license identifier
SPDX released version 3 of their license list (https://spdx.org/licenses/),
which changed the FSF licenses to explicitly end in -only or -or-later
instead of relying on an easy to miss + symbol.
Bug: T183858
Change-Id: I8db3866344b31b86d18094b356b7a72289bd13fa