incr.comp.: Implement force_from_dep_node() in a macro.

[michaelwoerister]

The ty::maps::plumbing::force_from_dep_node() procedure (introduced in #44901) is manually implemented right now. This is unfortunate, since it contains an exhaustive match over all DepKinds and the implementation could be done almost mechanically. We should try to move the implementation into define_maps! or define_dep_nodes!.

[cjgillot]

This can be closed now.