console_linux_2_4 adds creation of the console link to the files target by figuring out which port is used for kernel debug. The commands of the files target will then create a symbolic link, /dev/console, to the serial port configured to be used for kernel debug in the latest used kernel configuration, kernelconfig.latest.
console_linux_2_4 is called from kernel(3), so if you call kernel(3) in your script, you should not call console_linux_2_4.