[llvm] [mlir] [mlir][ods] Allow sharding of op definitions (PR #89423)

[Mehdi Amini via llvm-commits]

joker-eph wrote:

> Can we apply this to the TestDialect as a proof of concept?

Actually I just see that this is what you do in the follow-up PR, so LGTM here

https://github.com/llvm/llvm-project/pull/89423