[llvm] [LLVM][DWARF] Add compilation directory and dwo name to TU in dwo section (PR #74909)

[David Blaikie via llvm-commits]

dwblaikie wrote:

> > Works for me/at least worth using it to experiment, see if it works for lldb, etc.
> > Maybe a comment in the DwarfDebug source explaining what these attributes might be useful for?
> 
> I don't think LLDB has support yet for this, and tombstoning in linker yet. I believe @clayborg was waiting until this is in trunk.

Yep yep - but I'm OK with tihs going in first. Sorry, didn't mean to request further testing/demonstrated value before it's committed - just that I think this is adequate to be committed, to facilitate further testing/development.

https://github.com/llvm/llvm-project/pull/74909