drm/nouveau/core: drop the pointer value in debug printk output

Makes the output slightly less useful, in that objects with the same
class handle can't be distinguished from each other now.

Upcoming commits will name objects with user-readable strings to fix
this problem.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --cc drivers/gpu/drm/nouveau/core/core/printk.c
Simple merge