hikey: update ddr initialization

Fix that DDR can't work at 533MHz. Now step to set DDR frequency
from 150MHz to 800MHz. DDR could work among these frequency, 150MHz,
266MHz, 400MHz, 533MHz and 800MHz.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
3 files changed