[llvm] [X86] Add alwaysILP tuning flag (PR #189034)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

> Actually, there might be something else to fix first.
> ...
> The `&&` clause is always true, so we always default to `createSourceListDAGScheduler`. With this fixed I have a test that will work here. Unfortunately there are 600+ test files affected.

Can you do that in a separate draft PR to let us see whats happening?

https://github.com/llvm/llvm-project/pull/189034