PCI: Set ->mask_pos correctly

The "+" operation has higher precedence than "?:" and ->msi_cap is
always non-zero here so the original statement is equivalent to:

    entry->mask_pos = PCI_MSI_MASK_64;

Which wasn't the intent.

[bhelgaas: my fault from 78b5a31]
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/msi.c

@@ -563,8 +563,10 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
 	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
 	entry->msi_attrib.pos		= dev->msi_cap;
 
-	entry->mask_pos = dev->msi_cap + (control & PCI_MSI_FLAGS_64BIT) ?
-		PCI_MSI_MASK_64 : PCI_MSI_MASK_32;
+	if (control & PCI_MSI_FLAGS_64BIT)
+		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_64;
+	else
+		entry->mask_pos = dev->msi_cap + PCI_MSI_MASK_32;
 	/* All MSIs are unmasked by default, Mask them all */
 	if (entry->msi_attrib.maskbit)
 		pci_read_config_dword(dev, entry->mask_pos, &entry->masked);