drm/amd/display: Implement CM dealpha and bias interfaces

Add vtable entries for de-alpha and bias color management interfaces.
Move piece-wise transfer function registers to a helper list for future
reuse.

Signed-off-by: Gary Kattan <gary.kattan@amd.com>
Reviewed-by: Nevenko Stupar <Nevenko.Stupar@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>