Bug#701148: linux-image-3.7-trunk-amd64: Regression - brightness controls do not work.

[David Smith <sidicas2@gmail.com>]

Summary:

3.2.0-4-amd64 (Wheezy):  Brightness controls work, get a popup indicator 
showing the brightness should be changing, dmesg says ACPI fails to 
switch the brightness.

3.6-trunk: Brightness controls work, get a popup indicator showing the 
brightness should be changing, dmesg says ACPI fails to switch the 
brightness.

3.7-trunk: Brightness controls do nothing, no popup indicator,  no ACPI 
failures about brightness in dmesg.

3.7-trunk+video.allow_duplicate=1: Brightness controls cause a popup 
indicator showing brightness should be changing, but the brightness 
doesn't change. no ACPI failures about brightness in dmesg.

3.6-trunk+video.allow_duplicate=1: Brightness controls cause a popup 
indicator showing brightness should be changing, but the brightness 
doesn't change.  dmesg says ACPI fails to switch the brightness.