[llvm] [llvm-dlltool] Implement the --identify option (PR #127465)

[Martin Storsjö via llvm-commits]

mstorsjo wrote:

@cjacek What do you think about backporting this one? It isn't a bugfix like that, but it's a quite small and selfcontained new option. (There's a case for Meson to use it.) For backporting, it would require cherrypicking both dcc08a17c781a5066ab17b9791e1c455f7cedbf7 and 1ca93b15482d3bfa1560b35960ab46fea65b3074.

https://github.com/llvm/llvm-project/pull/127465