e1000e: Use pcie_capability_read_word() for reading LNKSTA

Use pcie_capability_read_word() for reading LNKSTA and remove the
custom define that matches to PCI_EXP_LNKSTA.

As only single user for cap_offset remains, replace it with a call to
pci_pcie_cap(). Instead of e1000_adapter, make local variable out of
pci_dev because both users are interested in it.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/e1000e/defines.h

@@ -678,7 +678,6 @@
 
 /* PCI/PCI-X/PCI-EX Config space */
 #define PCI_HEADER_TYPE_REGISTER     0x0E
-#define PCIE_LINK_STATUS             0x12
 
 #define PCI_HEADER_TYPE_MULTIFUNC    0x80
 

drivers/net/ethernet/intel/e1000e/mac.c

@@ -15,18 +15,15 @@
  **/
 s32 e1000e_get_bus_info_pcie(struct e1000_hw *hw)
 {
+	struct pci_dev *pdev = hw->adapter->pdev;
 	struct e1000_mac_info *mac = &hw->mac;
 	struct e1000_bus_info *bus = &hw->bus;
-	struct e1000_adapter *adapter = hw->adapter;
-	u16 pcie_link_status, cap_offset;
+	u16 pcie_link_status;
 
-	cap_offset = adapter->pdev->pcie_cap;
-	if (!cap_offset) {
+	if (!pci_pcie_cap(pdev)) {
 		bus->width = e1000_bus_width_unknown;
 	} else {
-		pci_read_config_word(adapter->pdev,
-				     cap_offset + PCIE_LINK_STATUS,
-				     &pcie_link_status);
+		pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &pcie_link_status);
 		bus->width = (enum e1000_bus_width)FIELD_GET(PCI_EXP_LNKSTA_NLW,
 							     pcie_link_status);
 	}