[mlir][linalg][bufferize] CallOps do not bufferize to memory writes

However, since CallOps have no aliasing OpResults, their OpOperands always bufferize out-of-place.

This change removes `bufferizesToMemoryWrite` from `CallOpInterface`. This method was called, but its return value did not matter.

Differential Revision: https://reviews.llvm.org/D114616