security/vuxml: Add CWE information

[trasz]

Summary

This updates "make newentry" to also include CWE information.
Requires VuXML 1.2.

[trasz]

Note that for now this requires new schema files, to be found at:

https://people.freebsd.org/~trasz/vuxml-12.dtd
https://people.freebsd.org/~trasz/vuxml-model-12.mod

Otherwise "make validate" will fail.

[philip]

This looks good to me, but please wait for the security team to discuss this before committing. I have no idea what (if any) downstream consumers we have and how this will affect them. We have not touched this schema since 2005.

[devnull_apt322.org]

This looks good to me from vuxml side.

But it might be interesting to take a look at the pkg_audit.c including cwe into structure and parse entry.