[llvm] [DWARF] Change to consistently print out abbrev code in .debug_names (PR #68353)

[David Blaikie via llvm-commits]

dwblaikie wrote:

Thanks for explaining. Changing the formatting layout of the name dumping seems not ideal - scoping the attributes makes it read as though they're part of an appreviation, which they aren't (they're part of the entry, using the abbrev as the encoding/schema).

So perhaps we can change only the case of the hex characters, rather than other aspects of the rendering.

It looks like the root cause of the divergence is that `raw_ostream::write_hex` explicitly uses lower case, and `llvm::operator<<(raw_ostream&, const HexNumber&)` gets implicit upper case.

Perhaps the latter should use the former and have the same behavior? Probably requires a bit of cleanup to other tests/usage, but hopefully it's feasible... 

https://github.com/llvm/llvm-project/pull/68353