[llvm] [BOLT] Improve handling of relocations targeting specific instructions (PR #66395)

[Vladislav Khmelevsky via llvm-commits]

yota9 wrote:

I'm not familiar yet with RISC asm, could you please describe why loading value from symbol results in text relocation (e.g. reference to the instruction)? Just interesting :) 
Overall it seems to me reasonable and the implementation is nice, LGTM. Let's wait Meta team suggestions though. 

https://github.com/llvm/llvm-project/pull/66395