Fix SoC identification issue on Marvell platforms

Marvell SoC identification function was called by SYSINIT on all armv7
platforms, which brakes platforms other than Marvell built with
GENERIC config. Fix this by shifting SoC identifying to Marvell platform
initialization.

Submitted by: Patryk Duda <pdk@semihalf.com>
Reviewed by: manu
Tested by: manu
Obtained from: Semihalf
Sponsored by: Stormshield