The Aristainetos and Aristainetos2 boards have only SoC compatible.

Cc: Heiko Schocher <hs@denx.de>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>