[mlir] Move the operation equivalence out of CSE and into OperationSupport

[rriddle]

Summary

This provides a general hash and comparison for checking if two operations are equivalent. This revision also optimizes the handling of result types to take advantage of how result types are stored on the operation.

Depends On D78892

[jpienaar]

Looks good as this is extracting existing function with some optimizations for common cases.