drm/amd/pp: Enable pp_set_power_profile_mode under manual mode

Only user enter manual performance mode, driver allow user
configure the sclk/mclk dpm parameters through sysfs
pp_power_profile_mode.

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