git: f6ae97673c28..b3392d84da5b - vendor/zstd - vendor branch updated

[Allan Jude]

The branch vendor/zstd has been updated by allanjude:

URL: https://cgit.FreeBSD.org/src/log/?id=f6ae97673c28..b3392d84da5b

b3392d84da5b Import zstd 1.5.2