Revert "ACPI / video: change acpi-video brightness_switch_enabled default to 0"

This reverts commit 886129a8eebeb (ACPI / video: change acpi-video
brightness_switch_enabled default to 0) as it is reported to cause
problems to happen.

Fixes: 886129a8eebeb (ACPI / video: change acpi-video brightness_switch_enabled default to 0)
Link: http://marc.info/?l=linux-acpi&m=140534286826819&w=2
Reported by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index c1b9aa8..e332e71 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3526,7 +3526,7 @@
 			the allocated input device; If set to 0, video driver
 			will only send out the event without touching backlight
 			brightness level.
-			default: 0
+			default: 1
 
 	virtio_mmio.device=
 			[VMMIO] Memory mapped virtio (platform) device.