Add a pass that checks wether everything was allocated to a certain core

[JosseVanDelm]

We ran into some difficult to debug behaviour because accelerator-specific code was launched on both cores as dispatch-regions was not working properly on our provided example, A linalg wrapped inside an scf.for.

I think we should enforce a legalize check on our IR before it leaves snax-opt to check whether all IR is properly allocated to a certain core to omit these types of errors.
Ideally the pass is extensible towards multiple types of accelerator/cpu combinations.