rockchip: Add core SoC start-up code

Add code for starting up U-Boot SPL and U-Boot proper. This is generic and
makes use of devices provided by the board- or SoC-specific code.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-rockchip/rk3288/Kconfig b/arch/arm/mach-rockchip/rk3288/Kconfig
new file mode 100644
index 0000000..26d5951
--- /dev/null
+++ b/arch/arm/mach-rockchip/rk3288/Kconfig
@@ -0,0 +1,6 @@
+if ROCKCHIP_RK3288
+
+config SYS_SOC
+	default "rockchip"
+
+endif