Add initial version of script for enabling and disabling console in FNGS
This is a part of the fix for issue [746-000797] Flash-N-Go System: Implement "Disable serial console"
The script is intended to enable and disable console in fngsystem:
- when the script is ran with --disable-console argument, a boot-alt.cfg will be adjusted to remove "console" argument from kernel command line;
- and when this script is ran with --enable-console argument, the console will be enabled again.
Example: sh /usr/share/yocto-install/fngsystem-console-update.sh --disable-console
Two other related MRs: