[llvm] [memprof] Add YAML read/write support to llvm-profdata (PR #118915)

[Carlo Cabrera via llvm-commits]

carlocab wrote:

Do you have a sense for approximately how many existing test cases would be simplified by adding this support? Or is this meant to support tests to be added in the future?

https://github.com/llvm/llvm-project/pull/118915