drm/todo: Updating logging todo

Jani has merged a new set of logging functions, which we hope to be
the One True solution now, pinky promises:

commit fb6c7ab8
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Tue Dec 10 14:30:43 2019 +0200

    drm/print: introduce new struct drm_device based logging macros

Update the todo entry to match the new preference.

v2: Fix spelling issue Sam noticed.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Wambui Karuga <wambui.karugax@gmail.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191219161722.2779994-1-daniel.vetter@ffwll.ch