The bulk of D142074 seems to have gotten overwritten due to some sort of merge conflict (afaict there's no record of it having been reverted intentionally). So this commit redoes those changes. In addition to the original changes, this commit also:
- moves the definition of getRankedTensorType (from Transforms/CodegenUtils.h to IR/SparseTensor.h), so that it can be used by IR/SparseTensorDialect.cpp.
- adds getMemRefType as another abbreviation.