The show_splash function called by the 20-debug-shell.sh script already
skips fbsplash when the device is configured to not use the framebuffer.
But the variable was not defined in the script. This is solved by
including the /etc/deviceinfo file.
Follow-up to !108, where this change got lost in the rebase.
* Changed usb-shell behavior, it wait for some user action before continue booting
* Rename usb-shell to debug-shell and changed port to 23
* Add `20-debug-shell.sh` script to static code analysis
* Enable eth0 interface in initramfs (qemu)
* Add additional script to run a shell in order to be able to kill it from a telnet session