AM335x ICEv2 contains a 2Gbit(128Mx16) of DDR3 SDRAM(MT41J128M16JT-125), capable of running at 400MHz. Adding this specific DDR configuration details running at 400MHz. Reviewed-by: Tom Rini <trini@konsulko.com> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>