drm/amd/display: Refactor DCN401 DCCG into component directory

drm/amd/display: Refactor DCN401 DCCG into component directory

[WHY]
Clean up the code that requires dccg to be in its own component.

[HOW]
Move all files under newly created dccg dir and fix the makefiles.

Acked-by: Alex Hung <alex.hung@amd.com>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Revalla Hari Krishna <Harikrishna.Revalla@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>