drm/vkms: Extend todo

Typed up all the items Rodrigo capture at the vkms workshop at
xdc2018:

https://etherpad.net/p/vkms_todo



v2: Review from Rodrigo.
- Add eBPF for atomic check, I forgot it.
- Improve spelling.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Haneen Mohammed <hamohammed.sa@gmail.com>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181003132103.29309-1-daniel.vetter@ffwll.ch