USB: core: Discard pm_runtime_put() return value

To allow the return type of pm_runtime_put() to be changed to void in the
future, modify usb_autopm_put_interface_async() to discard the return
value of pm_runtime_put().

That value is merely used in a debug comment printed by the function in
question and it is not a particularly useful piece of information
because pm_runtime_put() does not guarantee that the device will be
suspended even if it successfully queues up a work item to check
whether or not the device can be suspended.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/5058509.GXAFRqVoOG@rafael.j.wysocki

Author: rafaeljw

drivers/usb/core/driver.c

@@ -1810,13 +1810,11 @@ EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
 void usb_autopm_put_interface_async(struct usb_interface *intf)
 {
 	struct usb_device	*udev = interface_to_usbdev(intf);
-	int			status;
 
 	usb_mark_last_busy(udev);
-	status = pm_runtime_put(&intf->dev);
-	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
-			__func__, atomic_read(&intf->dev.power.usage_count),
-			status);
+	pm_runtime_put(&intf->dev);
+	dev_vdbg(&intf->dev, "%s: cnt %d\n",
+			__func__, atomic_read(&intf->dev.power.usage_count));
 }
 EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);