nouveau/gsp: don't check devinit disable on GSP.

GSP should be handling this and I can see no evidence in opengpu
driver that this register should be touched.

Fixed acceleration on 2080 Ti GPUs.

Fixes: 15740541

 ("drm/nouveau/devinit/tu102-: prepare for GSP-RM")

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240314014521.2695233-1-airlied@gmail.com