d3d10core/tests: Add acceptable error code for Win7

[Henri Verbeet]

2009/8/26 Ge van Geldorp <ggeldorp at vmware.com>:
>      hr = IDXGIFactory_EnumAdapters(factory, 0, &adapter);
> -    ok(SUCCEEDED(hr), "EnumAdapters failed, hr %#x\n", hr);
> +    ok(SUCCEEDED(hr) || hr == DXGI_ERROR_NOT_FOUND, "EnumAdapters failed, hr %#x\n", hr);

Is that in a VM? It's fine to skip the test if there are no adapters,
but I don't think that's supposed to happen on real hardware.