devel/mcpp: update to 2.7.2.1, fix CVE

ChangeLog: https://github.com/museoa/mcpp/compare/2.7.2...2.7.2.1

Fixes CVE-2019-14274: heap-based buffer overflow

• Base Score: 5.5 MEDIUM
• Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

PR: 280962
Reported by: alster@vinterdalen.se
MFH: 2024Q3 (security fix)
Security: CVE-2019-14274