ARM: exynos: fix regression for Origen4210

ARM: exynos: fix regression for Origen4210

The do_lowlevel_init() function includes certian CA15 specific L2 cache
configuration which is only applicable on Exynos5420 and members of its
family. Fix the regression on Origen4210 by skipping the Exynos5420
specific portions of the code.

Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Tested-by: Przemyslaw Marczak <p.marczak@samsung.com>
Acked-by: Przemyslaw Marczak <p.marczak@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>