ARM: hisilicon: hikey: Implement reset_cpu() for hikey.

This allows the reset command to reset the board from
u-boot.

=> reset
resetting ...
INFO:    BL1: 0xf9810000 - 0xf9818000 [size = 32768]
NOTICE:  Booting Trusted Firmware
NOTICE:  BL1: v1.1(debug):7fb9b0e
NOTICE:  BL1: Built : 17:06:41, Apr 19 2016

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/hisilicon/hikey/hikey.c b/board/hisilicon/hikey/hikey.c
index 3f0a0cc..752ee6f 100644
--- a/board/hisilicon/hikey/hikey.c
+++ b/board/hisilicon/hikey/hikey.c
@@ -414,8 +414,8 @@
 	gd->bd->bi_dram[0].size = PHYS_SDRAM_1_SIZE;
 }
 
-/* Use the Watchdog to cause reset */
 void reset_cpu(ulong addr)
 {
-	/* TODO program the watchdog */
+	writel(0x48698284, &ao_sc->stat0);
+	wfi();
 }