Instead of configuring kernel-to-cubin/rocdl lowering through callbacks, introduce a base class that target-specific passes can derive from.
Put the base class in GPU/Transforms, according to the discussion in D98203.
The mlir-cuda-runner will go away shortly, and the mlir-rocdl-runner as well at some point. I therefore kept the existing code path working and will remove it in a separate step.
Depends On D98168
This is not public API but rather an implementation detail. Could it move to an implementation header in lib?