platform/x86: think-lmi: add debug_cmd

Many Lenovo BIOS's support the ability to send a debug command which
is useful for debugging and testing unreleased or early features.

Adding support for this feature as a module parameter.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20210817001501.293501-1-markpearson@lenovo.com


Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>