These are identified by misc-include-cleaner. I've filtered out those
that break builds. Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.
Relax the assumption that alloc op always has allocation at
`getResult(0)`, allow to use `optimize-allocation-liveness` pass for
custom ops with >1 results. Ops with multiple allocations are not
handled here yet.
Adding a pass that is expected to run after the deallocation pipeline
and will move buffer deallocations right after their last user or
dependency, thus optimizing the allocation liveness.
