drm/nouveau/kms: add 8.1Gbps DP link rate

This was already done in dcb.c inside nvkm, but the other parser did not
get the update.

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