[llvm] [DFAJumpThreading] Enable DFAJumpThread by default. (PR #157646)

[Usman Nadeem via llvm-commits]

UsmanNadeem wrote:

@XChy Yes, I can volunteer to be a co-maintainer as well.

We are also interested in seeing DFA Jumpthreading being enabled by default. I think some others have also shown interest in it as well. See my previous patch: https://github.com/llvm/llvm-project/pull/83033 

https://github.com/llvm/llvm-project/pull/157646