[clang] [llvm] [mlir] [CMake] Add dependent project mode for Flang's MLIR (PR #221724)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> The idea/hope is that projects downstream could ALSO take advantage of this build time opt.

I don't think this is something that should be solved at this level. The PR exists to minimize dependencies that the user did not specify they want, but are needed. If you want downstream users to have minimal builds I'd look into LLVM distribution components, which are basically just big bags of CMake targets under a common name, https://llvm.org/docs/BuildingADistribution.html

https://github.com/llvm/llvm-project/pull/221724