drm/amdgpu: remove perf level dpm in one-VF

On Navi12 platform, node power_dpm_force_performance_level
doesn't work correctly in one-VF mode with at least three
smu messages not supported:
SMU_MSG_SetSoftMaxByFreq
SMU_MSG_SetSoftMinByFreq
SMU_MSG_TransferTableDram2Smu

Reviewed-by: Kevin Wang <kevin1.wang@amd.com>
Signed-off-by: Wenhui Sheng <Wenhui.Sheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c

@@ -1945,7 +1945,7 @@ static ssize_t amdgpu_set_thermal_throttling_logging(struct device *dev,
 
 static struct amdgpu_device_attr amdgpu_device_attrs[] = {
 	AMDGPU_DEVICE_ATTR_RW(power_dpm_state,				ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF),
-	AMDGPU_DEVICE_ATTR_RW(power_dpm_force_performance_level,	ATTR_FLAG_BASIC|ATTR_FLAG_ONEVF),
+	AMDGPU_DEVICE_ATTR_RW(power_dpm_force_performance_level,	ATTR_FLAG_BASIC),
 	AMDGPU_DEVICE_ATTR_RO(pp_num_states,				ATTR_FLAG_BASIC),
 	AMDGPU_DEVICE_ATTR_RO(pp_cur_state,				ATTR_FLAG_BASIC),
 	AMDGPU_DEVICE_ATTR_RW(pp_force_state,				ATTR_FLAG_BASIC),