drm/amd/display: move clock programming from set_bandwidth to dccg

This change moves dcn clock programming(with exception of dispclk)
into dccg. This should have no functional effect.

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>