drm/amd/display: Enable timing sync on DCN32

Missed enabling timing sync on DCN32 because DCN32 has a different DML
param.

Tested-by: Mark Broadworth <mark.broadworth@amd.com>
Reviewed-by: Martin Leung <Martin.Leung@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alvin Lee <Alvin.Lee2@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>