[clang] Switch builtin strings to use string tables (PR #118734)

[Chandler Carruth via cfe-commits]

chandlerc wrote:

So, the builder came back up, and is now passing without this landing...

Here is the first build after it came back up: https://lab.llvm.org/buildbot/#/builders/46/builds/9173

And I went through the output and found a specific test that was failing, and it seems to pass?
```
PASS: Clang :: AST/builtins-arm-strex-rettype.c (433 of 81898)
```

It looks like the builder is now using MSVC version 14.29.30133 -- so that might explain it. This maybe means that there is some issue with later patch releases of 14.28 (in Visual Studio v16.9 as I understand it)?

Are all of your builders OK moving to 14.29 (Visual Studio 16.11 from my reading)?

https://github.com/llvm/llvm-project/pull/118734