[llvm] [StandardInstrumentation] Add YieldCallback to NewPM (PR #86561)

[Arthur Eubanks via llvm-commits]

aeubanks wrote:

`LLVMContext::yield` isn't a great API. it claims that it doesn't need to be called, plus you can only have one callback. could you instead add your own pass instrumentation downstream that does what you want it to do? pass instrumentation is more principled in when it'll be called. and with the work on the new PM for codegen, hopefully you can retire your yield callback and always use pass instrumentation at some point

https://github.com/llvm/llvm-project/pull/86561