Update to 1.7.2

• Add LICENSE_FILE

Changes: https://github.com/richardlehane/siegfried/blob/v1.7.2/CHANGELOG.md
PR: 218403
Submitted by: Steffen <steffen@fritz.wtf> (maintainer)
Approved by: lme (mentor)
Differential Revision: https://reviews.freebsd.org/D10294