nouveau: fix devinit paths to only handle display on GSP.

This reverts:
nouveau/gsp: don't check devinit disable on GSP.
and applies a further fix.

It turns out the open gpu driver, checks this register,
but only for display.

Match that behaviour and in the turing path only disable
the display block. (ampere already only does displays).

Fixes: 5d4e8ae6

 ("nouveau/gsp: don't check devinit disable on GSP.")
Reviewed-by: Danilo Krummrich <dakr@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240408064243.2219527-1-airlied@gmail.com