drm/nv30: Fix PFB init for nv31.

Fixes a regression introduced by 58bbb63720c8997e0136fe1884101e7ca40d68fd
(fdo bug 29324).

Reported-by: Johannes Obermayr <johannesobermayr@gmx.de>
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
1 file changed