prep_pci_direct_decompose_tag
pc->pc_decompose_tag = prep_pci_direct_decompose_tag;
prep_pci_direct_decompose_tag(v, tag, &bus, &device, &function);
prep_pci_direct_decompose_tag(v, tag, &bus, &device, &function);
void prep_pci_direct_decompose_tag(void *, pcitag_t, int *, int *, int *);