Since when the driver was converted to use the bus-based WMI
interface, the old GUID-based WMI functions are not used anymore.
Update the error message to avoid confusing users.

Compile-tested only.

Fixes: 75c487fc ("platform/x86: intel-wmi-sbl-fw-update: Use bus-based WMI interface")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240106224126.13803-1-W_Armin@gmx.deReviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>