Revert "intel_agp: fix stolen mem range on G33"

This reverts commit f443675a, which
breaks horribly if you aren't running an unreleased xf86-video-intel
driver out of git.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Zhenyu Wang <zhenyu.z.wang@intel.com>
Acked-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>