p54pci: don't return zero on failure paths in p54p_probe()

If pci_set_dma_mask() or pci_set_consistent_dma_mask() fails in p54p_probe(),
it breaks off initialization, deallocates all resources, but returns zero.
Similar issue is if check for returned value of pci_resource_len() fails.

The patch implements proper error code propagation.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/p54/p54pci.c

@@ -559,6 +559,7 @@ static int p54p_probe(struct pci_dev *pdev,
 	mem_len = pci_resource_len(pdev, 0);
 	if (mem_len < sizeof(struct p54p_csr)) {
 		dev_err(&pdev->dev, "Too short PCI resources\n");
+		err = -ENODEV;
 		goto err_disable_dev;
 	}
 
@@ -568,8 +569,10 @@ static int p54p_probe(struct pci_dev *pdev,
 		goto err_disable_dev;
 	}
 
-	if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) ||
-	    pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32))) {
+	err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+	if (!err)
+		err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+	if (err) {
 		dev_err(&pdev->dev, "No suitable DMA available\n");
 		goto err_free_reg;
 	}