Use debugfs API directly instead of drm middle layer.
v2: * checkpatch.pl: use '0444' instead of S_IRUGO.
* remove S_IFREG from mode.
* remove mode variable.
Signed-off-by: Nirmoy Das <nirmoy.das@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>