git: aaf1213c6f70..61e1a12bb6c3 - vendor/bc - vendor branch updated

[Stefan Eßer]

The branch vendor/bc has been updated by se:

URL: https://cgit.FreeBSD.org/src/log/?id=aaf1213c6f70..61e1a12bb6c3

61e1a12bb6c3 vendor/bc: import version 6.3.1