USB: usb_wwan: remove comment from close

Remove superfluous and cryptic comment from close.

It should be obvious that we're balancing the autopm_put in open (and
that operation already mentions the autopm_get done in the USB serial
core).
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/usb_wwan.c

@@ -450,7 +450,6 @@ void usb_wwan_close(struct usb_serial_port *port)
 		usb_kill_urb(portdata->out_urbs[i]);
 	usb_kill_urb(port->interrupt_in_urb);
 
-	/* balancing - important as an error cannot be handled*/
 	usb_autopm_get_interface_no_resume(serial->interface);
 }
 EXPORT_SYMBOL(usb_wwan_close);