nvidia-driver and bus_memio.h

The removal of bus_memio.h broke the nvidia driver.

-- 
Russell A. Jackson
Rudin's Law:
	If there is a wrong way to do something, most people will
	do it every time.

Rudin's Second Law:
	In a crisis that forces a choice to be made among alternative
	courses of action, people tend to choose the worst possible
	course.