[llvm] [TableGen] Detect invalid -D arguments and fail (PR #102813)

[Rahul Joshi via llvm-commits]

jurahul wrote:

@MaskRay Ping. @s-barannikov maybe we can wait for a couple of days for any additional feedback, else commit? To that end, can you approve?

https://github.com/llvm/llvm-project/pull/102813