security/afl++: Update 4.40c => 5.03c

Update LICENSE as afl++ contains AGPLv3+ code since 5.00c.

Changelog:
https://github.com/AFLplusplus/AFLplusplus/blob/v5.03c/docs/Changelog.md

PR: 293797
Sponsored by: UNIS Labs
Co-authored-by: Vladimir Druzenko <vvd@FreeBSD.org>