Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Move LIBADD lines from usr.bin/clang/*/Makefile one level up

Some utilities under usr.bin/clang were only linked to libz, while most
others were linked to libz and libzstd. Make this consistent, and remove
repetition, by moving these LIBADD lines to usr.bin/clang/clang.prog.mk
and usr.bin/clang/clang.prog.mk.

MFC after: 3 days

Merge llvm-project main llvmorg-14-init-10223-g401b76fdf2b3

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14-init-10223-g401b76fdf2b3.

PR: 261742
MFC after: 2 weeks

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR: 255570
MFC after: 6 weeks

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Update build glue for a build of clang plus the extra tools (enabled via
MK_CLANG_EXTRAS).

Update llvm and clang build glue to make MK_CLANG_EXTRAS=yes and
MK_CLANG_FULL=yes work.

Update llvm tool manpages, and llvm-mca.1.

Update build blue to make WITH_CLANG_EXTRAS and WITH_CLANG_FULL work.

Move all sources from the llvm project into contrib/llvm-project.

This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.

Updating the vendor area to match this layout is next.

Update build glue for a build of clang plus the extra tools (enabled via
MK_CLANG_EXTRAS).

Update llvm and clang build glue to make MK_CLANG_EXTRAS=yes and
MK_CLANG_FULL=yes work.

Update llvm tool manpages, and llvm-mca.1.

Update build blue to make WITH_CLANG_EXTRAS and WITH_CLANG_FULL work.