PCI: Use pci_is_pcie() to simplify code

Use pci_is_pcie() instead of pci_find_capability() to simplify code.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 7ef0f86..c90d0f8 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -641,8 +641,7 @@
 		return;
 	}
 
-	pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
-	if (pos) {
+	if (pci_is_pcie(bridge)) {
 		u32 linkcap;
 		u16 linksta;