[llvm] [BOLT] Add support for safe-icf (PR #116275)

[Alexander Yermolovich via llvm-commits]

ayermolo wrote:

> I've minimized bolt/test/X86/icf-safe-icp.test. Please use that as an example to reduce other tests.

I don't think this is the right approach for bolt. 
You removed code example of how to re-generate the test, and from test itself it's not clear what is being tested.

https://github.com/llvm/llvm-project/pull/116275