Bug#1080464: Fix feature check for clang-19+

[Matthias Klose]

Package: src:xtensor
Version: 0.25.0-1
Severity: important
Tags: sid trixie patch

Fix feature check for clang-19+, taken from upstream.

Patch at
https://launchpadlibrarian.net/747418683/xtensor_0.25.0-1_0.25.0-1ubuntu1.diff.gz