ram: rk3328: use common sdram driver

RK3328 has a similar controller and phy with PX30, so we can use the
common driver for it and remove the duplicate codes.

Signed-off-by: YouMin Chen <cym@rock-chips.com>
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/drivers/ram/rockchip/Makefile b/drivers/ram/rockchip/Makefile
index 4bfc3d9..b477f70 100644
--- a/drivers/ram/rockchip/Makefile
+++ b/drivers/ram/rockchip/Makefile
@@ -9,6 +9,6 @@
 obj-$(CONFIG_ROCKCHIP_RK3188) = sdram_rk3188.o
 obj-$(CONFIG_ROCKCHIP_RK322X) = sdram_rk322x.o
 obj-$(CONFIG_ROCKCHIP_RK3288) = sdram_rk3288.o
-obj-$(CONFIG_ROCKCHIP_RK3328) = sdram_rk3328.o
+obj-$(CONFIG_ROCKCHIP_RK3328) = sdram_rk3328.o sdram_pctl_px30.o sdram_phy_px30.o
 obj-$(CONFIG_RAM_RK3399) += sdram_rk3399.o
 obj-$(CONFIG_ROCKCHIP_SDRAM_COMMON) += sdram_common.o