PCI: pciehp: Make queue_interrupt_event() void

Nobody looks at the return value from queue_interrupt_event(), so errors
were silently ignored.  Convert it to a "void" function and note the error
in the dmesg log.

No functional change except the new message.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NRajat Jain <rajatja@google.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>

drivers/pci/hotplug/pciehp_ctrl.c

@@ -37,21 +37,20 @@
 
 static void interrupt_event_handler(struct work_struct *work);
 
-static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
+static void queue_interrupt_event(struct slot *p_slot, u32 event_type)
 {
 	struct event_info *info;
 
 	info = kmalloc(sizeof(*info), GFP_ATOMIC);
-	if (!info)
-		return -ENOMEM;
+	if (!info) {
+		ctrl_err(p_slot->ctrl, "dropped event %d (ENOMEM)\n", event_type);
+		return;
+	}
 
+	INIT_WORK(&info->work, interrupt_event_handler);
 	info->event_type = event_type;
 	info->p_slot = p_slot;
-	INIT_WORK(&info->work, interrupt_event_handler);
-
 	queue_work(p_slot->wq, &info->work);
-
-	return 0;
 }
 
 u8 pciehp_handle_attention_button(struct slot *p_slot)