dmar_alloc_dev_scope
dmaru->devices = dmar_alloc_dev_scope((void *)(drhd + 1),
rmrru->devices = dmar_alloc_dev_scope((void *)(rmrr + 1),
atsru->devices = dmar_alloc_dev_scope((void *)(atsr + 1),
satcu->devices = dmar_alloc_dev_scope((void *)(satc + 1),
extern void *dmar_alloc_dev_scope(void *start, void *end, int *cnt);