drm/amd/display: enable eDP DSC seamless boot support

drm/amd/display: enable eDP DSC seamless boot support

[Why]
VBIOS supports DSC for seamless boot on newer hardware.
Reading hardware state allows proper DSC validation without breaking
existing boot display.

[What]
Remove DSC block for boot timing validation and implement hardware state
reading to populate DSC configuration from VBIOS-configured state.
Enhance dsc_read_state function in DCN401 to read additional
DSC parameters.

Reviewed-by: Yihan Zhu <yihan.zhu@amd.com>
Signed-off-by: Mohit Bawa <Mohit.Bawa@amd.com>
Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>