rockchip: rk3308: Move cru and grf include files to arch-rockchip

Move cru_rk3308.h and grf_rk3308.h to arch-rockchip to match path used
for all other Rockchip SoCs.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/drivers/ram/rockchip/sdram_rk3308.c b/drivers/ram/rockchip/sdram_rk3308.c
index 10828e8..2643662 100644
--- a/drivers/ram/rockchip/sdram_rk3308.c
+++ b/drivers/ram/rockchip/sdram_rk3308.c
@@ -7,8 +7,8 @@
 #include <dm.h>
 #include <ram.h>
 #include <syscon.h>
-#include <asm/arch/grf_rk3308.h>
 #include <asm/arch-rockchip/clock.h>
+#include <asm/arch-rockchip/grf_rk3308.h>
 #include <asm/arch-rockchip/sdram.h>
 
 struct dram_info {