This patch adds a flag to `secureboot.database.Generate` to append the
Microsoft UEFI secure boot DB and KEK certificates to the appropriate
ESLs, in addition to complimentary command line flags.
This patch also includes a copy of said Microsoft certificates. The
certificates are downloaded from an official Microsoft repo.
Signed-off-by: Jean-Francois Roy <jf@devklog.net>
Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>