pci_bridge: Remove duplicate IRQ swizzle function

pci_bridge_dev_map_irq_fn() is identical to pci_swizzle_map_irq_fn(),
which is now the default for all PCI bridges.  We can therefore remove
this function and the pci_bridge_map_irq() call that used it.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/pci_bridge_dev.c

@@ -36,21 +36,12 @@ struct PCIBridgeDev {
 };
 typedef struct PCIBridgeDev PCIBridgeDev;
 
-/* Mapping mandated by PCI-to-PCI Bridge architecture specification,
- * revision 1.2 */
-/* Table 9-1: Interrupt Binding for Devices Behind a Bridge */
-static int pci_bridge_dev_map_irq_fn(PCIDevice *dev, int irq_num)
-{
-    return (irq_num + PCI_SLOT(dev->devfn)) % PCI_NUM_PINS;
-}
-
 static int pci_bridge_dev_initfn(PCIDevice *dev)
 {
     PCIBridge *br = DO_UPCAST(PCIBridge, dev, dev);
     PCIBridgeDev *bridge_dev = DO_UPCAST(PCIBridgeDev, bridge, br);
     int err;
 
-    pci_bridge_map_irq(br, NULL, pci_bridge_dev_map_irq_fn);
     err = pci_bridge_initfn(dev);
     if (err) {
         goto bridge_error;