The backlight and lcd subsystems can be notified by the framebuffer layer
of blanking events.  However, these subsystems, as a whole, can function
independently from the framebuffer layer.  But in order to enable to the
lcd and backlight subsystems, the framebuffer has to be compiled also,
effectively sucking in a huge amount of unneeded code.

To prevent dependency problems, separate out the framebuffer notification
mechanism from the framebuffer layer and permanently link it to the kernel.

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>