[llvm] Instruction: avoid crash in getStableDebugLoc when `this` isn't a DbgInfoIntrinsic (PR #66266)

[Augie Fackler via llvm-commits]

durin42 wrote:

Also, if it helps: I did manage to get some dump() equivalent, but it means nothing to me: https://reviews.llvm.org/D159485#4646085

https://github.com/llvm/llvm-project/pull/66266