[clang] [llvm] [IR] Don't use TrackingMDNodeRef for DebugLoc (PR #200649)

[Florian Hahn via cfe-commits]

https://github.com/fhahn commented:

I think this introduced a Use-After-Free when intrinsics with debug metadata get auto-upgraded (an example is `Transforms/LoopVectorize/X86/reg-usage-debug.ll`). Put up a fix: https://github.com/llvm/llvm-project/pull/200779

https://github.com/llvm/llvm-project/pull/200649