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

[via llvm-commits]

arrowten wrote:

@jh7370 I've finished the implementation for `.debug_abbrev`. Quick question about behavior: `llvm-dwarfdump --output-style=JSON --debug-abbrev <exe_file>` correctly dumps the abbreviation section after my changes, but for now if a user runs `llvm-dwarfdump --output-style=JSON <exe_file>`, i.e. without the section flag, should it suppress the `.debug_abbrev` JSON output entirely and show a warning that the sections have not been implemented or should it handle it differently?

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