[llvm] [LLVM] Specialize test suites for `TableGen` and `FileCheck` to use smaller set of dependencies (PR #155929)

[Chris B via llvm-commits]

llvm-beanz wrote:

I understand the utility of what you're trying to do here, but I worry that if we extrapolate this pattern out across the test subdirectories we're going to create an unmanageable mess.

Every subdirectory under the test suite gets its own target, and if each target gets configured for its own dependency subset manually we're creating a real mess to maintain.

https://github.com/llvm/llvm-project/pull/155929