[llvm] [mlir] [CMake] Do not set CMP0116 explicitly to old (PR #90385)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

Looks like this is failing in the Windows CI. Not entirely sure why. I was unable to reproduce the issue locally in a couple of different configurations.

https://github.com/llvm/llvm-project/pull/90385