git: c6bcacc7c9d8..4b5393dfb492 - vendor/llvm-project/release-18.x - vendor branch updated

From: Dimitry Andric <dim_at_FreeBSD.org>
Date: Sun, 09 Jun 2024 15:11:02 UTC
The branch vendor/llvm-project/release-18.x has been updated by dim:

URL: https://cgit.FreeBSD.org/src/log/?id=c6bcacc7c9d8..4b5393dfb492

4b5393dfb492 Vendor import of llvm-project branch release/18.x llvmorg-18.1.7-0-g768118d1ad38.