drm/amd/display: Revert "program k1/k2 divider for virtual signal for DCN32"

[Why & How]
This reverts commit e6cf22ef since it
causes a SubVP related regression: "Switching between windowed video and
fullscreen can intermittently cause black screen"

Fixes: e6cf22ef ("drm/amd/display: program k1/k2 divider for virtual signal for DCN32")
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>