[llvm] [BOLT] [PowerPC] Port (PR #140894)

[Vladislav Khmelevsky via llvm-commits]

yota9 wrote:

Hello @kostasalv ! Thank you for your work. But from my side I would say that maybe this port is too basic. I mean I would expect at least hello world test to be compiled and optimized to submit this PR. This is my IMHO, it's up to @maksfb to decide at the end, but maybe it would be possible to add couple of relocations & etc support to at least run couple very basic C (or even asm) tests with BOLT? thank you!

https://github.com/llvm/llvm-project/pull/140894