drm/TODO: Clarify DRM_DEV_* conversion

Not everyone agrees this is the best thing, so make it really clear
that maintainers need to be asked first, then the conversion. We've
had a few newbies that did this the other way round, got their patches
rejected, which isn't the best newbie experience.

Cc: Sean Paul <seanpaul@chromium.org>
Acked-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171030131536.11654-1-daniel.vetter@ffwll.ch

Documentation/gpu/todo.rst

@@ -179,6 +179,10 @@ don't do this, drivers used dev_info/warn/err to make this differentiation. We
 now have DRM_DEV_* variants of the drm print macros, so we can start to convert
 those drivers back to using drm-formwatted specific log messages.
 
+Before you start this conversion please contact the relevant maintainers to make
+sure your work will be merged - not everyone agrees that the DRM dmesg macros
+are better.
+
 Contact: Sean Paul, Maintainer of the driver you plan to convert
 
 Core refactorings