- Deleted content about old spdx.bbclass.
- Added usage of meta-spdxscanner.
(From yocto-docs rev: 59908cecb5283ebdea1800c4d86a6310a45159bf)
Signed-off-by: Lei Maohui <leimaohui@cn.fujitsu.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>