Remove ReduceOp::accumulator (#52196)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/52196
A reduction does not need to know the buffer into which its
result will be written. This change gets us closer to being able to
create reductions inside Compute, where we have access to the tensor
axes.
ghstack-source-id: 121813071
Test Plan: test_tensorexpr
Reviewed By: ZolotukhinM
Differential Revision: D26420107
Pulled By: bertmaher
fbshipit-source-id: c8d8a99649adfd6de56fe53a728f5aa034a84f13
