Allow multiple bootstrap entries for a single video driver with the same name, which internally allows preferential and fallback init conditions while hiding the implementation details from applications (e.g. applications will just see "wayland", regardless of whether it's using the preferred or fallback driver list entry).
If a driver is requested, all instances of it in the list will be tried before reporting failure, and client applications programmatically enumerating the video drivers will be presented with a deduplicated list of entries.
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