msi_map
msi_map(map->im_msi_base, addr, data, cpuid);
.msi_map = ioapic_abi_msi_map,
.msi_map = icu_abi_msi_map,
msi_map(map->im_msi_base, addr, data, cpuid);
void msi_map(int intr, uint64_t *addr, uint32_t *data, int cpuid);
MachIntrABI.msi_map(irq, addr, data, cpuid);
void (*msi_map) /* addr/data for MSI on cpu */