[clang] [llvm] [MC,llvm-readobj,yaml2obj] Support CREL relocation format (PR #91280)

[Peter Smith via cfe-commits]

https://github.com/smithp35 commented:

Some initial comments based on a read of the ELFObjectFile. I haven't got as far as the test and tools.

One general thought is whether it is worth adding in some more constants. For example:
```
if (B & 1)
```
Could be something like:
```
if (B & DeltaSymbolMask)
```

I'll keep looking, likely next week.

https://github.com/llvm/llvm-project/pull/91280