vmware_vga: clean up

use NULL instead of 0 for pci_register_device() argument
for consistency. Any other caller uses NULL.
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

hw/vmware_vga.c

@@ -1217,7 +1217,7 @@ void pci_vmsvga_init(PCIBus *bus)
     /* Setup PCI configuration */
     s = (struct pci_vmsvga_state_s *)
         pci_register_device(bus, "QEMUware SVGA",
-                sizeof(struct pci_vmsvga_state_s), -1, 0, 0);
+                sizeof(struct pci_vmsvga_state_s), -1, NULL, NULL);
     pci_config_set_vendor_id(s->card.config, PCI_VENDOR_ID_VMWARE);
     pci_config_set_device_id(s->card.config, SVGA_PCI_DEVICE_ID);
     s->card.config[PCI_COMMAND]		= 0x07;		/* I/O + Memory */