drm/amd/display: implement support for DID2.0 dsc passthrough

[Why]
Some panels contain active converters (e.g. DP to MIPI) which only support
restricted DSC configurations.  DID2.0 adds support for such displays to
explicitly define per timing BPP restrictions on DSC.  Ignoring these
restrictions leads to blackscreen.

[How]
Add parsing in DID2.0 parser to get this bpp info.
Add support in DSC module to constraint target bpp based
on this info.

Signed-off-by: Jun Lei <jun.lei@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Acked-by: Anson Jacob <Anson.Jacob@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>