s390x/pci: code cleanup

Now that each S390 PCI device uses an IO region as MSIX region. The
code in s390_translate_iommu() will never be triggered. Let's remove
it.
Signed-off-by: NYi Min Zhao <zyimin@linux.vnet.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

hw/s390x/s390-pci-bus.c

@@ -404,17 +404,6 @@ static IOMMUTLBEntry s390_translate_iommu(MemoryRegion *iommu, hwaddr addr,
 
     DPRINTF("iommu trans addr 0x%" PRIx64 "\n", addr);
 
-    /* s390 does not have an APIC mapped to main storage so we use
-     * a separate AddressSpace only for msix notifications
-     */
-    if (addr == ZPCI_MSI_ADDR) {
-        ret.iova = addr;
-        ret.translated_addr = addr;
-        ret.addr_mask = 0xfff;
-        ret.perm = IOMMU_RW;
-        return ret;
-    }
-
     if (addr < pbdev->pba || addr > pbdev->pal) {
         return ret;
     }