[3.17] main/lighttpd: security upgrade to 1.4.76
- detect VU#421644 HTTP/2 CONTINUATION Flood
- avoid CVE-2024-3094 xz supply chain attack
Ref https://www.lighttpd.net/2024/4/12/1.4.76/
Ref !64038 (merged)
Ref https://www.lighttpd.net/2024/4/12/1.4.76/
Ref !64038 (merged)