[llvm] [llvm-dwarfdump] Added --output-style option for controlling output format (PR #216559)

[James Henderson via llvm-commits]

https://github.com/jh7370 approved this pull request.

LGTM, but as noted this shouldn't be merged until we have concrete implementations that this flag will impact.

https://github.com/llvm/llvm-project/pull/216559