PCI: Delete unnecessary NULL pointer checks

The pci_dev_put() function tests whether its argument is NULL and then
returns immediately.  Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

drivers/pci/hotplug/cpci_hotplug_core.c

@@ -214,8 +214,7 @@ static void release_slot(struct hotplug_slot *hotplug_slot)
 
 	kfree(slot->hotplug_slot->info);
 	kfree(slot->hotplug_slot);
-	if (slot->dev)
-		pci_dev_put(slot->dev);
+	pci_dev_put(slot->dev);
 	kfree(slot);
 }