clang(1)/llvm updated to version 16

In a long series of
commits,
Robert Nagy (robert@)
updated
clang(1)/llvm
in -current to version 16:

CVSROOT:	/cvs
Module name:	src
Changes by:	robert@cvs.openbsd.org	2023/11/11 11:01:31

Log message:
    import of llvm from LLVM 16.0.6
    
    Status:
    
    Vendor Tag:	LLVM
    Release Tags:	LLVM_16_0_6
    
    U src/gnu/llvm/llvm/.clang-format
    U src/gnu/llvm/llvm/.clang-tidy
    U src/gnu/llvm/llvm/.gitattributes
[…]
    U src/gnu/llvm/llvm/utils/vscode/llvm/syntaxes/ll.tmLanguage.yaml
    U src/gnu/llvm/llvm/utils/yaml-bench/CMakeLists.txt
    U src/gnu/llvm/llvm/utils/yaml-bench/YAMLBench.cpp
    
    67 conflicts created by this import.
    Use the following command to help the merge:
    
    cvs checkout -jLLVM:yesterday -jLLVM src/gnu/llvm/llvm

Naturally, this has involved supporting work elsewhere in base,
and in ports.