PCI: Delete unnecessary NULL pointer checks

---
 drivers/pci/pci-acpi.c     | 3 +--
 drivers/pci/probe.c        | 3 +--
 drivers/pci/search.c       | 3 +--
 drivers/pci/xen-pcifront.c | 3 +--
 4 files changed, 4 insertions(+), 8 deletions(-)
 
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 @@ static void pci_acpi_wake_dev(struct work_struct *work)
 	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);
 }
 
 /**
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 5ed9930..eb927c0 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -87,8 +87,7 @@ static void release_pcibus_dev(struct device *dev)
 {
 	struct pci_bus *pci_bus = to_pci_bus(dev);
 
-	if (pci_bus->bridge)
-		put_device(pci_bus->bridge);
+	put_device(pci_bus->bridge);
 	pci_bus_remove_resources(pci_bus);
 	pci_release_bus_of_node(pci_bus);
 	kfree(pci_bus);
diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index a81f413..a20ce7d 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -271,8 +271,7 @@ static struct pci_dev *pci_get_dev_by_id(const struct pci_device_id *id,
 			      match_pci_dev_by_id);
 	if (dev)
 		pdev = to_pci_dev(dev);
-	if (from)
-		pci_dev_put(from);
+	pci_dev_put(from);
 	return pdev;
 }
 
diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
index 116ca37..f01b26d 100644
--- a/drivers/pci/xen-pcifront.c
+++ b/drivers/pci/xen-pcifront.c
@@ -596,8 +596,7 @@ static pci_ers_result_t pcifront_common_process(int cmd,
 	pcidev = pci_get_bus_and_slot(bus, devfn);
 	if (!pcidev || !pcidev->driver) {
 		dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
-		if (pcidev)
-			pci_dev_put(pcidev);
+		pci_dev_put(pcidev);
 		return result;
 	}
 	pdrv = pcidev->driver;