[mlir][linalg][bufferize][NFC] Specify bufferize traversal in `bufferize`

The interface method `bufferize` controls how (and it what order) nested ops are traversed. This simplifies bufferization of scf::ForOps and scf::IfOps, which used to need special rules in scf::YieldOp.

Differential Revision: https://reviews.llvm.org/D114057