powerpc/eeh: Fix null deref for devices removed during EEH

If a device is removed during EEH processing (either by a driver's
handler or as part of recovery), it can lead to a null dereference
in eeh_pe_report_edev().

To handle this, skip devices that have been removed.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/eeh_driver.c

@@ -281,6 +281,10 @@ static void eeh_pe_report_edev(struct eeh_dev *edev, eeh_report_fn fn,
 	struct pci_driver *driver;
 	enum pci_ers_result new_result;
 
+	if (!edev->pdev) {
+		eeh_edev_info(edev, "no device");
+		return;
+	}
 	device_lock(&edev->pdev->dev);
 	if (eeh_edev_actionable(edev)) {
 		driver = eeh_pcid_get(edev->pdev);