Auto merge of rust-lang#120985 - Kobzol:linux-update-host-llvm, r=<try>

Update host LLVM on x64 Linux to LLVM 18

Opening for a perf. run.

r? `@ghost`

Author: bors

src/ci/docker/host-x86_64/dist-x86_64-linux/build-clang.sh

@@ -4,7 +4,7 @@ set -ex
 
 source shared.sh
 
-LLVM=llvmorg-17.0.4
+LLVM=llvmorg-18.1.0-rc2
 
 mkdir llvm-project
 cd llvm-project