spdx.bbclass: improved stability, fixed SPDX compliance issues. Changes are reflected in licenses.conf.
The previous version could crash on dead links in the rootfs, or if the manifest directory did not
exist. The generated files were also not compliant with the SPDX specification, for example file
entries did not always start with the FileName tag, time stamps were incorrectly formatted etc.
Stability issues are addressed by added checks, originally written by Johan Thelin
<johan.thelin@pelagicore.com>, who never upstreamed them. I've also added an option for getting full
SPDX output from FOSSology, i.e. not only for all files, but for the package as well, including
license references. License refs are required in order to process the output by SPDXTools. For that
reason, this option defaults to true.
Signed-off-by: Tobias Olausson <tobias.olausson@pelagicore.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
