drm/amdgpu: keep stolen memory on picasso

otherwise screen corrupts during modprobe.
Signed-off-by: Flora Cui <flora.cui@amd.com>
Reviewed-by: Feifei Xu <Feifei.Xu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c

@@ -626,6 +626,7 @@ static bool gmc_v9_0_keep_stolen_memory(struct amdgpu_device *adev)
 	case CHIP_VEGA10:
 		return true;
 	case CHIP_RAVEN:
+		return (adev->pdev->device == 0x15d8);
 	case CHIP_VEGA12:
 	case CHIP_VEGA20:
 	default: