Revert "[IRSim][IROutliner] Adding the extraction basics for the IROutliner."

Reverting commit due to address sanitizer errors.

> Extracting the similar regions is the first step in the IROutliner.
> 
> Using the IRSimilarityIdentifier, we collect the SimilarityGroups and
> sort them by how many instructions will be removed.  Each
> IRSimilarityCandidate is used to define an OutlinableRegion.  Each
> region is ordered by their occurrence in the Module and the regions that
> are not compatible with previously outlined regions are discarded.
> 
> Each region is then extracted with the CodeExtractor into its own
> function.
> 
> We test that correctly extract in:
> test/Transforms/IROutliner/extraction.ll
> test/Transforms/IROutliner/address-taken.ll
> test/Transforms/IROutliner/outlining-same-globals.ll
> test/Transforms/IROutliner/outlining-same-constants.ll
> test/Transforms/IROutliner/outlining-different-structure.ll
> 
> Reviewers: paquette, jroelofs, yroux
> 
> Differential Revision: https://reviews.llvm.org/D86975

This reverts commit bf899e89.