Expose some monotonically increasing architecture level ID

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Developers often have problems understanding core capabilities - too many models with unclear variant numbering. For example, it's not clear that a Mali-G52 similar in capability to a Mali-G76 - based on numbering alone, you might think it's more similar to a Mali-G51.

We must expose a monotonically increasing architecture variant index, which can be used to broadly classify generational capabilities. The ID value doesn't matter, but must be stable once used.