[llvm] [DebugInfo] Add DILayerLoc/DILayerLocList and DILocation irlayers operand (PR #215666)

[Eric Christopher via llvm-commits]

https://github.com/echristo approved this pull request.

A couple of nits, nothing blocking. Wait for a couple of the others to approve as well.

https://github.com/llvm/llvm-project/pull/215666