drm/amdgpu/virtual_dce: Add vega20 support

Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NFeifei Xu <Feifei.Xu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Reviewed-by: NHawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

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

@@ -473,6 +473,7 @@ static int dce_virtual_hw_init(void *handle)
 		break;
 	case CHIP_VEGA10:
 	case CHIP_VEGA12:
+	case CHIP_VEGA20:
 		break;
 	default:
 		DRM_ERROR("Virtual display unsupported ASIC type: 0x%X\n", adev->asic_type);