[llvm] [DFAJumpThreading] Enable the pass by default (PR #83033)

[Usman Nadeem via llvm-commits]

UsmanNadeem wrote:

> @UsmanNadeem Given what the pass does, you should aim for 0.1% first-order impact. (IIRC the cost of the original implementation was in that ballpark.)

After the recent patches to fix the compile time, the costs now look reasonable: https://llvm-compile-time-tracker.com/compare.php?from=2903df02fb3c057849aaa796a91289b01950a5f0&to=110e07154887a0c0f8705a7a3ffb2d25aa59f94f&stat=instructions:u 

> stage1-O3: (+0.08%)
> stage1-ReleaseLTO-g: (+0.04%)
> stage1-ReleaseThinLTO: (+0.15%)
> clang build: (+0.05%)

https://github.com/llvm/llvm-project/pull/83033