rockchip: sdram: update the sys_reg to sys_reg2

We are using sys_reg2 and sys_reg3 as ddr cap info, sync the variable
name to what we real use to avoid confuse people.

Signed-off-by: YouMin Chen <cym@rock-chips.com>
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
1 file changed