drm/amd/pm: centralize all pp_dpm_xxx attribute nodes update cb

centralize all pp_dpm_xxx attr nodes into
pp_dpm_clk_default_attr_update() function.
Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>