git: f6a891c2b422..2690f2feae43 - vendor/xz - vendor branch updated

From: Xin LI <delphij_at_FreeBSD.org>
Date: Mon, 23 Jan 2023 00:51:32 UTC
The branch vendor/xz has been updated by delphij:

URL: https://cgit.FreeBSD.org/src/log/?id=f6a891c2b422..2690f2feae43

2690f2feae43 Vendor import of xz 5.4.1 (trimmed)