Grub2 password configuration

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grub2 password configuration

grub2-password was configured by using following steps as root user:

1. Run 'grub2-mkpasswd-pbkdf2' and get password hash of desired password
2. Edit '/etc/grub.d/40_custom' file and append:

   set superusers="root"
   password root <password-hash>

3. Run 'grub2-mkconfig > /etc/grub2.cfg'

Note that these steps just caused password prompt to appear during 'e' (edit) or 'c' (command-line) request at grub, but the authentication never succeeded.