This fixes a bug that prevent my amd64 box from booting;
numa_default_policy was __init however it's called like this in
init/main.c:

        free_initmem();
        unlock_kernel();
        system_state = SYSTEM_RUNNING;
        numa_default_policy();


eg after free_initmem(). This resulted in it being reused/freed and that
gives a nasty oops.