nvme_pcicfg_map_bar
status_t status = nvme_pcicfg_map_bar(devhandle, bar, false, mapped_addr);
ret = nvme_pcicfg_map_bar(ctrlr->pci_dev, 0, 0, &addr);
int nvme_pcicfg_map_bar(void *devhandle, unsigned int bar, bool read_only,