[llvm] [BOLT] Fix -print-relocations option (PR #101895)

[via llvm-commits]

linsinan1995 wrote:

> Could you please add small test with BOLT --print-relocations option? I see we have 0 now for this :)

Sorry for the delay. I made some updates

1. --print-relocations now works with --print-disasm, which helps debug relocation-related issues.
2. also refactor X86, since X86 relocations are also not sequentially numbered.

https://github.com/llvm/llvm-project/pull/101895