git: 5d58a5157172..6f49f5cdde1c - vendor/bc - vendor branch updated

From: Stefan Eßer <se_at_FreeBSD.org>
Date: Wed, 06 Oct 2021 21:29:37 UTC
The branch vendor/bc has been updated by se:

URL: https://cgit.FreeBSD.org/src/log/?id=5d58a5157172..6f49f5cdde1c

6f49f5cdde1c vendor/bc: update to version 5.1.1