PCI/AER: Log AER IRQ when claiming Root Port

Add a log message when we enable AER on a Root Port and the hierarchy below
it.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/pcie/aer/aerdrv.c b/drivers/pci/pcie/aer/aerdrv.c
index 60e63d6..dea186a 100644
--- a/drivers/pci/pcie/aer/aerdrv.c
+++ b/drivers/pci/pcie/aer/aerdrv.c
@@ -312,8 +312,8 @@
 	rpc->isr = 1;
 
 	aer_enable_rootport(rpc);
-
-	return status;
+	dev_info(device, "AER enabled with IRQ %d\n", dev->irq);
+	return 0;
 }
 
 /**