[Nouveau] Put acpi/backlight code into kernel

[schmirrwurst at googlemail.com]

Hi, 

I'm trying to bring devs to support for backlight on nv50 cards for above 1 
year, without any success
A lot of laptop (from mac, hp, samsung) doesn't have laptop_panel in hal, and 
therefore no support for acpi/backlight..., and no entry in /proc/acpi/video 
nor /sys/class/backlight

Kernel team is not reacting, hal team won't fix, devicekit need standardise 
i/o...

I've tried nouveau, the acpi/backlight support works pretty well, but the 
driver itself is unusable for lambda users, it needs some times...
So I'm asking if someone could put the backlight code in a kernel module, or 
in the kernel itself, for people to have backlight support even when using 
nvidia driver or nv, or vesa... ???