Rename result_0 to result in dialect ops bindings

[mofeing]

Right now, ops with result_0 kwarg put it like that because they either have multiple results or name it like that in the defining tblgen.

We haven't found any case of result_1 or higher, and for the multiple results a tuple of MLIR.IR.Types could be passed instead. What do you think @jumerckx? should we rename it?

I think it would make calling the interface to ops a lil bit more pleasant and less error-prone.