[compiler-rt] [llvm] [cmake] Honor CMAKE_VERBOSE_MAKEFILE when building external projects (PR #75749)

[Fangrui Song via llvm-commits]

https://github.com/MaskRay approved this pull request.

I have checked that `CMAKE_VERBOSE_MAKEFILE`  does not affect Ninja, so perhaps most people will not observe anything.

https://github.com/llvm/llvm-project/pull/75749