append_str
newstr = append_str(kernel, BFLAG, " ");
kernel = append_str(newstr, "console=", " ");
newstr = append_str(kernel, console_dev, "");
newstr = append_str(kernel, "console=", ",");
kernel = append_str(newstr, console_dev, "");
newstr = append_str(kernel, BFLAG, " ");
newstr = append_str(kernel, "ttya-mode='", delim);
kernel = append_str(newstr, "'", serial_config[0]);
newstr = append_str(kernel, "ttyb-mode='", delim);
kernel = append_str(newstr, "'", serial_config[1]);
newstr = append_str(kern_bargs, serial_config[0], " ");
newstr = append_str(kern_bargs, serial_config[1], " ");
newstr = append_str(kern_bargs, extra_args, " ");