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.
Reviewed By: aartbik
Differential Revision: https://reviews.llvm.org/D142503
9916ab03f1