rockchip: rk3288: add arch_cpu_init in spl

Add arch_cpu_init() in SPL for soc related init, and
move configure_l2ctlr() into it.
The arch_cpu_init() only need to run once, so no need
to run in TPL.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/mach-rockchip/rk3288/rk3288.c b/arch/arm/mach-rockchip/rk3288/rk3288.c
index 7941ca6..5300650 100644
--- a/arch/arm/mach-rockchip/rk3288/rk3288.c
+++ b/arch/arm/mach-rockchip/rk3288/rk3288.c
@@ -10,11 +10,15 @@
 
 int arch_cpu_init(void)
 {
+#ifdef CONFIG_SPL_BUILD
+	configure_l2ctlr();
+#else
 	/* We do some SoC one time setting here. */
 	struct rk3288_grf * const grf = (void *)GRF_BASE;
 
 	/* Use rkpwm by default */
 	rk_setreg(&grf->soc_con2, 1 << 0);
+#endif
 
 	return 0;
 }