drm/amd/display: support new PMFW interface to disable Z9 only

[Why]
Need to disable Z9 on configurations that only support Z10

[How]
Support new PMFW interface to disable Z9

Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>