lkdtm: Add kernel version to failure hints

In an effort to keep as much information in once place as possible in
CI logs, report the kernel version and architecture in the failure hints.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: kernelci@groups.io
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210818174855.2307828-4-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>