USB: fix up sparse lock warning in whiteheat driver

Yeah, the locking is still all fucked up, but at least it's
not _obviously_ wrong anymore.  It still needs to be fixed 
properly one of these days...
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/usb/serial/whiteheat.c

@@ -1114,11 +1114,11 @@ static int firm_send_command (struct usb_serial_port *port, __u8 command, __u8 *
 	command_port->write_urb->transfer_buffer_length = datasize + 1;
 	command_port->write_urb->dev = port->serial->dev;
 	retval = usb_submit_urb (command_port->write_urb, GFP_KERNEL);
-	spin_unlock_irqrestore(&command_info->lock, flags);
 	if (retval) {
 		dbg("%s - submit urb failed", __FUNCTION__);
 		goto exit;
 	}
+	spin_unlock_irqrestore(&command_info->lock, flags);
 
 	/* wait for the command to complete */
 	wait_event_interruptible_timeout(command_info->wait_command,