PCI/pciehp: Use PCI Express Capability accessors

Use PCI Express Capability access functions to simplify pciehp.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
diff --git a/drivers/pci/hotplug/pciehp_acpi.c b/drivers/pci/hotplug/pciehp_acpi.c
index 376d70d..24d709b 100644
--- a/drivers/pci/hotplug/pciehp_acpi.c
+++ b/drivers/pci/hotplug/pciehp_acpi.c
@@ -81,16 +81,12 @@
 /* Dummy driver for dumplicate name detection */
 static int __init dummy_probe(struct pcie_device *dev)
 {
-	int pos;
 	u32 slot_cap;
 	acpi_handle handle;
 	struct dummy_slot *slot, *tmp;
 	struct pci_dev *pdev = dev->port;
 
-	pos = pci_pcie_cap(pdev);
-	if (!pos)
-		return -ENODEV;
-	pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &slot_cap);
+	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 	if (!slot)
 		return -ENOMEM;