PCI: Delete unnecessary NULL pointer checks

The functions pci_dev_put(), pci_pme_wakeup_bus(), and put_device() return
immediately if their argument is NULL.  Thus the test before the call is
not needed.

Remove these unnecessary tests.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 6ebf8ed..3542150 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -322,8 +322,7 @@
 	pci_wakeup_event(pci_dev);
 	pm_runtime_resume(&pci_dev->dev);
 
-	if (pci_dev->subordinate)
-		pci_pme_wakeup_bus(pci_dev->subordinate);
+	pci_pme_wakeup_bus(pci_dev->subordinate);
 }
 
 /**