drm/i915: Fix ILK GPU reset domain bits

We're using the reset domains bits for g4x on ilk. But on ilk those bits
actually shifted by one bit. Fix it up so that we use the correct bits.

We were actually always writing 0x2 to the reset domain bits, which
is a reserved value. In practice it looks like the hardware ignores that
value since nothing happens if I write that value when there's a 3D
workload running. Writing the _correct_ render domain value actually
makes the GPU stop.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>