drm/nouveau: resume display if any later suspend bits fail

If either idling channels or suspending the fence were to fail, the
display would never be resumed. Also if a client fails, resume the fence
(not functionally important, but it would potentially leak memory).

See https://bugs.freedesktop.org/show_bug.cgi?id=70213

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