git: 956197bcea3a..12eff5f0d8b7 - vendor/xz - vendor branch updated

From: Xin LI <delphij_at_FreeBSD.org>
Date: Sun, 04 May 2025 07:08:06 UTC
The branch vendor/xz has been updated by delphij:

URL: https://cgit.FreeBSD.org/src/log/?id=956197bcea3a..12eff5f0d8b7

12eff5f0d8b7 Vendor import of xz 5.8.1 (trimmed)