toshiba_acpi: Refuse to load on machines with buggy INFO implementations

Several Satellite models have a buggy implementation of the INFO method
that causes ACPI exceptions when executed:

 ACPI Error: Result stack is empty! State=ffff88012d70f800 (20110413/dswstate-98)
 ACPI Exception: AE_AML_NO_RETURN_VALUE, Missing or null operand (20110413/dsutils-646)
 ACPI Exception: AE_AML_NO_RETURN_VALUE, While creating Arg 0 (20110413/dsutils-763)
 ACPI Error: Method parse/execution failed [\_SB_.VALZ.GETE] (Node ffff880131175eb0), AE_AML_NO_RETURN_VALUE (20110413/psparse-536)
 ACPI Error: Method parse/execution failed [\_SB_.VALZ.INFO] (Node ffff880131175ed8), AE_AML_NO_RETURN_VALUE (20110413/psparse-536)
 toshiba_acpi: ACPI INFO method execution failed
 toshiba_acpi: Failed to query hotkey event

All known machines with this implementation also have a WMI interface
with event GUID 59142400-C6A3-40FA-BADB-8A2652834100 which is not seen
on any other models. Refuse to load toshiba_acpi on machines with this
guid.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

drivers/platform/x86/Kconfig

@@ -569,6 +569,7 @@ config TOPSTAR_LAPTOP
 config ACPI_TOSHIBA
 	tristate "Toshiba Laptop Extras"
 	depends on ACPI
+	depends on ACPI_WMI
 	select LEDS_CLASS
 	select NEW_LEDS
 	depends on BACKLIGHT_CLASS_DEVICE