drm/amd/display: DSC Slice height debugfs write entry

[Why]
We need to be able to specify slice height for any connector's DSC

[How]
Overwrite computed parameters in dsc_cfg, with the value needed/
Overwrites for both SST and MST connectors, but in different places, but the process is identical. Overwrites only if DSC is decided to be enabled on that connector.

Signed-off-by: Eryk Brol <eryk.brol@amd.com>
Signed-off-by: Mikita Lipski <mikita.lipski@amd.com>
Reviewed-by: Mikita Lipski <Mikita.Lipski@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>