dzn: use ID3D10Blob instead of ID3DBlob

In the C interface, there's no such alias.

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15816>

src/microsoft/vulkan/dzn_device.cpp

@@ -1795,7 +1795,7 @@ dzn_device_create_root_sig(dzn_device *device,
 {
    dzn_instance *instance =
       container_of(device->vk.physical->instance, dzn_instance, vk);
-   ID3DBlob *sig, *error;
+   ID3D10Blob *sig, *error;
 
    if (FAILED(instance->d3d12.serialize_root_sig(desc,
                                                  &sig, &error))) {