Some DEFAULT_MODULEs in tree have dependencies of their own. This is
usually done for aliases of init modules, and do not have dependencies
themselves.
This adds the final stage to dependency resolutions where DEFAULT_MODULEs
dependencies MAY be included. These included modules MUST NOT have
dependencies themselves.
This allows for modules to disable DEFAULT_MODULEs during dependencies
resolution independent of the inclusion order.
auto_init and periph_init modules are moved to this outer-loop, allowing
therefore for modules to disable them during the dependency resolution
