[Intel-gfx] [PATCH v7 i-g-t 2/4] kms_writeback: Add initial writeback tests

[Simon Ser]

> > +   igt_output_set_prop_value(output, IGT_CONNECTOR_WRITEBACK_OUT_FENCE_PTR, (uint64_t)out_fence_ptr);
>
> On ARM (32bits), this cast creates a compilation error since the
> pointer size isn't an uint64_t.

Does casting to uintptr_t before uint64_t fix it?