[llvm] [DebugInfo][InstrRef] Index DebugVariables and some DILocations (PR #99318)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `ml-opt-dev-x86-64` running on `ml-opt-dev-x86-64-b2` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/137/builds/1969

Here is the relevant piece of the build log for the reference:
```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)

```

https://github.com/llvm/llvm-project/pull/99318