drm/amd/powerplay: disable gfxoff for navi14

gfxoff doesn't work on navi14 yet, so disable it for now
Signed-off-by: Xiaojie Yuan <xiaojie.yuan@amd.com>
Reviewed-by: Jack Xiao <Jack.Xiao@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/powerplay/amdgpu_smu.c

@@ -559,6 +559,9 @@ static int smu_early_init(void *handle)
 	smu->pm_enabled = !!amdgpu_dpm;
 	mutex_init(&smu->mutex);
 
+	if (adev->asic_type == CHIP_NAVI14)
+		adev->pm.pp_feature &= ~PP_GFXOFF_MASK;
+
 	return smu_set_funcs(adev);
 }