Ensure that the mallocator are really inactive when running MC

Ensure that the mallocator are really inactive when running MC

- before, they were created during the preinit and then destroyed when
  MC was activated.
- now, they are created inactive, and activated when the configuration
  stops if MC is still not activated.
- this mandates some changes around the initialization mechanism in
  the whole stack.
  - one hint that it was a good idea is that before, _surf_init_status
    were never reaching the value 2 (meaning "config now forbidden",
    according to the preexisting asserts).
  - Now this value is set from surf_routing when the first element of
    platform is created. This is a horrible hack intermixing the
    layers, but it was already accredited by the parser that
    configuration could occur until the first <AS>, but no later.
  - we now would need a proper way of increasing the init level of
    simgrid.

I hope that this change did not break anything, but much more work
would be mandated to clean the init mess properly.