platform/x86: fix asus-wmi build error

Fix build error in asus_wmi.c when ASUS_WMI=y and ACPI_VIDEO=m
by preventing that combination.

  drivers/built-in.o: In function `asus_wmi_probe':
  asus-wmi.c:(.text+0x65ddb4): undefined reference to `acpi_video_unregister'
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/platform/x86/Kconfig

@@ -504,6 +504,7 @@ config ASUS_WMI
 	depends on BACKLIGHT_CLASS_DEVICE
 	depends on RFKILL || RFKILL = n
 	depends on HOTPLUG_PCI
+	depends on ACPI_VIDEO || ACPI_VIDEO = n
 	select INPUT_SPARSEKMAP
 	select LEDS_CLASS
 	select NEW_LEDS