USB: serial: mos7840: drop redundant urb context check

The bulk-in URB context is set to the driver-data struct at open and is
never cleared so drop the redundant check in the completion callback.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

drivers/usb/serial/mos7840.c

@@ -500,17 +500,13 @@ static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
 
 static void mos7840_bulk_in_callback(struct urb *urb)
 {
+	struct moschip_port *mos7840_port = urb->context;
 	int retval;
 	unsigned char *data;
 	struct usb_serial *serial;
 	struct usb_serial_port *port;
-	struct moschip_port *mos7840_port;
 	int status = urb->status;
 
-	mos7840_port = urb->context;
-	if (!mos7840_port)
-		return;
-
 	if (status) {
 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
 		mos7840_port->read_urb_busy = false;