git: 52a5ec1b178f..898b46e93011 - vendor/bc - vendor branch updated

[Stefan Eßer]

The branch vendor/bc has been updated by se:

URL: https://cgit.FreeBSD.org/src/log/?id=52a5ec1b178f..898b46e93011

898b46e93011 vendor/bc: upgrade to version 6.7.6