The `-buffer-deallocation` pass is not compatible with One-Shot
Bufferize and has been replaced with the Ownership-based Buffer
Deallocation pass about 1.5 years ago. To clean up the code base, this
commit removes the deprecated `buffer-deallocation` pass. All uses of
this deprecated pass within MLIR have already been migrated.
Note for LLVM integration: If you depend on this pass, migrate to the
Ownership-based Buffer Deallocation pass or copy the pass to your
codebase. For details, see
https://discourse.llvm.org/t/psa-bufferization-new-buffer-deallocation-pipeline/73375.
Move the documentation of the ownership-based buffer deallocation pass
to a separate file. Also improve the documentation a bit and insert a
figure that explains the `bufferization.dealloc` op (copied from the
tutorial at the LLVM Dev Summit 2023).
