drm/todo: Update drm_gem_object_funcs todo even more

I rushed merging this a bit too much, and Noralf pointed out that
we're a lot better already and have made great progress.

Let's try again.

v2: Fix typo spotted by Eric Engestrom.

Fixes: 8db420ac ("drm/todo: Improve drm_gem_object funcs todo")
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190618140241.19856-1-daniel.vetter@ffwll.ch