drm/amd/display: update header files

[why]
update header files, and remove not used register access marco

Reviewed-by: Hansen Dsouza <hansen.dsouza@amd.com>
Acked-by: Pavle Kotarac <Pavle.Kotarac@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>