pci_bridge: manually destroy memory regions within PCIBridgeWindows

The regions are destroyed and recreated on configuration space accesses.
We need to destroy them before the containing PCIBridgeWindows object
is freed.
Reported-by: NGonglei <arei.gonglei@huawei.com>
Reported-by: NKnut Omang <knut.omang@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/pci/pci_bridge.c

@@ -219,6 +219,12 @@ static void pci_bridge_region_del(PCIBridge *br, PCIBridgeWindows *w)
 
 static void pci_bridge_region_cleanup(PCIBridge *br, PCIBridgeWindows *w)
 {
+    object_unparent(OBJECT(&w->alias_io));
+    object_unparent(OBJECT(&w->alias_mem));
+    object_unparent(OBJECT(&w->alias_pref_mem));
+    object_unparent(OBJECT(&w->alias_vga[QEMU_PCI_VGA_IO_LO]));
+    object_unparent(OBJECT(&w->alias_vga[QEMU_PCI_VGA_IO_HI]));
+    object_unparent(OBJECT(&w->alias_vga[QEMU_PCI_VGA_MEM]));
     g_free(w);
 }