Just a stub that indicates the system has booted in secure boot mode.
Used for testing the driver:
https://lore.kernel.org/all/20211019080608.283324-1-joel@jms.id.au/
Signed-off-by: Joel Stanley <joel@jms.id.au>
[ clg: - Fixed typo
- Adjusted Copyright dates ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>