This patch introduces a more general helper for identifying
elementwise-mappable operations. The existing utility,
`isElementwiseMappableOpOnRankedTensors`, only accepted operations when
all operands were ranked tensors. In practice, many elementwise
operations in MLIR allow mixing tensor operands with scalars.
The new helper relaxes the restriction by accepting operands that are
either ranked tensors or “scalar-like” types.