This change inserts a few extension point callbacks in the
DefaultFIROptimizerPassPipeline. As an example usage of callbacks in the
FIR optimizer pipeline, the FIRInlinerCallback is now used to register
the default MLIR inliner pass in flang-new, tco, and bbc compilation
flows. Other compilation flows can use these callbacks to add extra
passes at different points of the pass pipeline.
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Co-authored-by: Vijay Kandiah <vkandiah@sky6.pgi.net>
86ab10c4d9
