drm/amd/pp: Add memory clock info display on Cz/St

show mclk info as in MHz on Cz/St as
0: 333Mhz *
1: 800Mhz

Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>