drm/amd/pm: inform SMU RLC status thus enable/disable DPM feature for vangogh

RLC is halted when system suspend/shutdown. However, due to DPM enabled, PMFW is
unaware of RLC being halted and will continue sending messages, which would
eventually cause an ACPI hang. Use the system_feature_control interface to
notify SMU the status of RLC (Normal/OFF) thus enable/disable DPM feature.

Signed-off-by: Xiaomeng Hou <Xiaomeng.Hou@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Lazar Lijo <Lijo.Lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>