Fix warnings of the form

  warning: right shift count >= width of type
by casting to long before shifting by HIGH_BITS_OFFSET.

drivers/serial/8250.c

@@ -1885,7 +1885,7 @@ static int __register_serial(struct serial_struct *req, int line)
 	port.line     = line;
 
 	if (HIGH_BITS_OFFSET)
-		port.iobase |= req->port_high << HIGH_BITS_OFFSET;
+		port.iobase |= (long) req->port_high << HIGH_BITS_OFFSET;
 
 	/*
 	 * If a clock rate wasn't specified by the low level

drivers/serial/core.c

@@ -593,7 +593,7 @@ static int uart_get_info(struct uart_info *info, struct serial_struct *retinfo)
 	tmp.line	    = port->line;
 	tmp.port	    = port->iobase;
 	if (HIGH_BITS_OFFSET)
-		tmp.port_high = port->iobase >> HIGH_BITS_OFFSET;
+		tmp.port_high = (long) port->iobase >> HIGH_BITS_OFFSET;
 	tmp.irq		    = port->irq;
 	tmp.flags	    = port->flags | info->flags;
 	tmp.xmit_fifo_size  = port->fifosize;