[llvm] [Instrumentation] Move test coverage in Transforms (NFC) (PR #108544)

[Antonio Frighetto via llvm-commits]

antoniofrighetto wrote:

> Note that the contents of `llvm/test/Transforms` are flattened, i.e. they directly contain `llvm/test/Transforms/GVN` rather than `llvm/Test/Transforms/Scalar/GVN`, etc. So if you wanted to make this "consistent" you'd have to move `llvm/test/Instrumentation/AddressSanitizer` to `llvm/test/Transforms/AddressSanitizer`, not `llvm/test/Transforms/Instrumentation/AddressSanitizer`. Or else we'd need a larger restructuring to make the test directory schemas line up.

OK, that's a good point. Note however, that one reasonably can still expect to find GVN tests under Transforms. What sort of surprised me was to find out that neither Instrumentation nor AddressSanitizer directories were under Transforms. Moving each single directory into Transforms was an idea but felt like it would flood Transforms unnecessarily.

https://github.com/llvm/llvm-project/pull/108544