cxgb4: Use PCI Express Capability accessors

Use PCI Express Capability access functions to simplify cxgb4 driver.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -3694,15 +3694,7 @@ static void __devinit print_port_info(const struct net_device *dev)
 
 static void __devinit enable_pcie_relaxed_ordering(struct pci_dev *dev)
 {
-	u16 v;
-	int pos;
-
-	pos = pci_pcie_cap(dev);
-	if (pos > 0) {
-		pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &v);
-		v |= PCI_EXP_DEVCTL_RELAX_EN;
-		pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, v);
-	}
+	pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_RELAX_EN);
 }
 
 /*

drivers/net/ethernet/chelsio/cxgb4/t4_hw.c

@@ -2741,11 +2741,9 @@ static void __devinit get_pci_mode(struct adapter *adapter,
 				   struct pci_params *p)
 {
 	u16 val;
-	u32 pcie_cap = pci_pcie_cap(adapter->pdev);
 
-	if (pcie_cap) {
-		pci_read_config_word(adapter->pdev, pcie_cap + PCI_EXP_LNKSTA,
-				     &val);
+	if (pci_is_pcie(adapter->pdev)) {
+		pcie_capability_read_word(adapter->pdev, PCI_EXP_LNKSTA, &val);
 		p->speed = val & PCI_EXP_LNKSTA_CLS;
 		p->width = (val & PCI_EXP_LNKSTA_NLW) >> 4;
 	}