ARM: dts: Fix cpu compatible value for s3c2416

The change corrects cpu compatible property to a defined one,
see Documentation/devicetree/bindings/arm/cpus.txt

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>