rockchip: rk3188: use DM timer instead of rk_timer

Disable rk_timer as SYS timer and use DM timer instead,
so that we can get a better timer framework, the rk_timer
is going to be clean after we conver to use DM timer or
ARM arch/generic timer.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Acked-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
index e1b0519..096dbac 100644
--- a/arch/arm/mach-rockchip/Makefile
+++ b/arch/arm/mach-rockchip/Makefile
@@ -40,8 +40,10 @@
 obj-$(CONFIG_$(SPL_TPL_)RAM) += sdram_common.o
 
 ifndef CONFIG_ARM64
+ifndef CONFIG_ROCKCHIP_RK3188
 obj-y += rk_timer.o
 endif
+endif
 
 obj-$(CONFIG_ROCKCHIP_RK3036) += rk3036/
 obj-$(CONFIG_ROCKCHIP_RK3128) += rk3128/