drm/amd/display: Enable backlight support for pre-DCE11 ASICs

Initializing ABM and DMCU modules for dce 80/81/83/100 as in DCE110
Adding constructors and destructors for each module.
Adding register list for DMCU in dce80 as some registers are missing
in dce80 from the basic list. DMCU is never used, so it would not have
any functional impact.

Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>