commit d5fb46e0 upstream.

If you managed to exceed the limit to switch to vmalloc, we'd use the
wrong free.
Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: d5b1a78a ("drm/vc4: Add support for drawing 3D frames.")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>