drm/nouveau: default to 8bpc for non-LVDS panels if EDID isn't useful

A few reports of bad behaviour since the autodetection defaulted to 6bpc,
lets fix this.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
1 file changed