vxge: use pci_dma_mapping_error to test return value

pci_dma_mapping_error should be used to test return value of
pci_map_single or pci_map_page.

Signed-off-by: Denis Kirjanov <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/vxge/vxge-main.c

···
 	dma_addr = pci_map_single(ring->pdev, rx_priv->skb_data,
 				rx_priv->data_size, PCI_DMA_FROMDEVICE);
 
-	if (dma_addr == 0) {
+	if (unlikely(pci_dma_mapping_error(ring->pdev, dma_addr))) {
 		ring->stats.pci_map_fail++;
 		return -EIO;
 	}