Merge llvm-project release/14.x llvmorg-14.0.4-0-g29f1039a7285

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-14.0.4-0-g29f1039a7285, aka 14.0.4 release.

PR: 261742
MFC after: 3 days

(cherry picked from commit 2a66634d1bc6d7401adafad4a3be7b9ac6bab8b3)

Bump versions llvm-project release/14.x llvmorg-14.0.4-0-g29f1039a7285

Somehow git rebase made this squashed commit disappear. Restore it.

PR: 261742
MFC after: 3 days

(cherry picked from commit ab9d54731f43bb6befae75e9fed64da98c9ae1b4)

Update rest of llvm-project build glue for 14.0.4

I completely forgot about updating the generated llvm-project config
files, which also contain version numbers, etc. Sorry for the churn.

PR: 261742
Fixes: ab9d54731f43
MFC after: 3 days

(cherry picked from commit 809922b01004daf627ad4b8d92c7f98eb579043c)

Add more old clang files to (Optional)ObsoleteFiles.inc

There were a few more libclang_rt libraries added recently, but not yet
listed in the ObsoleteFiles.inc lists.

MFC after: 3 days

(cherry picked from commit 5e383e360314c875fee648b386493b0dcde5c5f3)