In order to remove the load and unload drm callbacks,
we need to reorder the init sequence to move all the drm
debugfs file handling.  Do this for rings.

Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>