selftests/livepatch: add sysfs test

Add a test for livepatch sysfs entries.

Signed-off-by: Song Liu <song@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20220902205208.3117798-3-song@kernel.org
3 files changed