drm/i915: Fix copy'n'pasteo that broke VT switch if flushing was non-empty.

Introduced in the "Avoid BUG_ONs on VT switch" commit.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/i915/i915_gem.c

@@ -2314,7 +2314,7 @@ i915_gem_idle(struct drm_device *dev)
 	while (!list_empty(&dev_priv->mm.flushing_list)) {
 		struct drm_i915_gem_object *obj_priv;
 
-		obj_priv = list_first_entry(&dev_priv->mm.active_list,
+		obj_priv = list_first_entry(&dev_priv->mm.flushing_list,
 					    struct drm_i915_gem_object,
 					    list);
 		obj_priv->obj->write_domain &= ~I915_GEM_GPU_DOMAINS;