drm/amd/display: Implement input gamma LUT

drm/amd/display: Implement input gamma LUT

1. Implemented dcn10_ipp_program_input_lut(), following the existing
   interface.
2. Added missing registers as needed
3. Change to REG_GET for *ram_select() funcs.
4. Removed gamma table init from DiagsDM::make_surface() for resolving
   CRC errors. Reason: Legacy LUT will be deprecated soon for Raven in
   favor of degamma/regamma.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>