drm: remove all control node code

drm: remove all control node code

With the ioctl and driver prep done, we can remove everything else.

Reviewed-by: Sean Paul <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Cc: Gustavo Padovan <[email protected]>
Cc: Maarten Lankhorst <[email protected]>
Cc: Sean Paul <[email protected]>
Cc: David Airlie <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]