The v7-A cluster is specific to the Aspeed 2600 series,
remove it from the common AspeedSoCState.

The ARM cores belong to the MP cluster, but the array
is currently used by TYPE_ASPEED2600_SOC. We'll clean
that soon, but for now keep it in Aspeed2600SoCState.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>