Revert "drivers: net: cpsw: remove hard coding bd ram for cpsw"

This reverts commit 2bf36ac638ab2db9f0295aa47064976eeebf80c1.
ARM: IGEP0033: Update timing to run DDR at 400MHz.

We can run the DDR at 400MHz, so update the timings for that purpose.

Signed-off-by: Enric Balletbo i Serra <eballetbo@iseebcn.com>