davinci: da850/omap-l138: Enable 4-bit ecc

This patch initializes the platform data to enable 4-bit
ecc support on DA850/OMAP-L138.

Signed-off-by: Sudhakar Rajashekhara <sudhakar.raj@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>