drm/amd/display: Fix DSC enable sequence

[Why]
DSC is enabled before reset link and potentially cause DSC enable fail problem.
[How]
Enable DSC after link is reseted

Signed-off-by: Mike Hsieh <chun-wei.hsieh@amd.com>
Acked-by: Bindu Ramamurthy <bindur12@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>