[llvm] [llvm][Dwarf] Add LanguageDescription API that accounts for version (PR #162048)

[David Blaikie via llvm-commits]

https://github.com/dwblaikie commented:

Be good to have some test coverage - either as a unit test, or if there's some useful way to render this data in llvm-dwarfdump, even better.

https://github.com/llvm/llvm-project/pull/162048