[llvm] [StaticDataLayout][PGO]Implement reader and writer change for data access profiles (PR #139997)

[Snehasish Kumar via llvm-commits]

snehasish wrote:

Thanks for the details and pointer to the lld patch @SharonXSharon. Some questions about the raw format changes --

1. I guess there should be a count associated with each `u64 MemBlockAddress`? 
2. What is `MemAddressOffset` in the `BinaryAccessHeader`?

I prefer evolving the raw format to support binary accesses instead of keeping them separate. I don't think the differences are significant enough to keep them separate. 

https://github.com/llvm/llvm-project/pull/139997