drm/amd/display: System black screen hangs on driver load

This reverts commit dbc43d5f
as it causes crash on driver load in some scenarios.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Martin Leung <Martin.Leung@amd.com>
Acked-by: Solomon Chiu <solomon.chiu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>