Update Gigabyte GA-6GXU's PCI table

Author: chun-awa

src/machine/m_at_slot2.c

@@ -54,7 +54,7 @@ machine_at_6gxu_init(const machine_t *model)
     machine_at_common_init(model);
 
     pci_init(PCI_CONFIG_TYPE_1);
-    pci_register_slot(0x00, PCI_CARD_NORTHBRIDGE, 0, 0, 0, 0);
+    pci_register_slot(0x00, PCI_CARD_NORTHBRIDGE, 1, 2, 3, 4);
     pci_register_slot(0x07, PCI_CARD_SOUTHBRIDGE, 1, 2, 3, 4);
     pci_register_slot(0x08, PCI_CARD_NORMAL,      1, 2, 3, 4);
     pci_register_slot(0x09, PCI_CARD_NORMAL,      2, 3, 4, 1);