rockchip: rk3328: Migrate to use common board file

Use common board file for board_init() and board_late_init(),
for Rockchip SoCs have very similar process.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Matwey V. Kornilov <matwey.kornilov@gmail.com>