serial: vr41xx_siu: delete double assignment

Delete successive assignments to the same location.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression i;
@@

*i = ...;
 i = ...;
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/vr41xx_siu.c

@@ -847,7 +847,6 @@ void __init vr41xx_siu_early_setup(struct uart_port *port)
 	siu_uart_ports[port->line].type = port->type;
 	siu_uart_ports[port->line].uartclk = SIU_BAUD_BASE * 16;
 	siu_uart_ports[port->line].mapbase = port->mapbase;
-	siu_uart_ports[port->line].mapbase = port->mapbase;
 	siu_uart_ports[port->line].ops = &siu_uart_ops;
 }