drm/nv40/mpeg: use the nv31-provided classes

Since nv40 only covers pre-nv44 now, it can use the nv31-provided
functions.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
4 files changed