sunxi: psci: Fix sunxi_power_switch on sun8i-r40 platform

linux system will die if we offline one of the cpu on R40 based board:
eg: echo 0 > /sys/devices/system/cpu/cpu3/online

The reason is that the R40 version of sunxi_cpu_set_power always passes
0 for the CPU number, so we turn off CPU0, regardless of what CPU the
CPU_OFF request came for.

Fix this by passing the proper CPU number, as there are proper power
clamp registers for every of the four cores.

Signed-off-by: qianfan Zhao <qianfanguijin@163.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/arch/arm/cpu/armv7/sunxi/psci.c b/arch/arm/cpu/armv7/sunxi/psci.c
index d1bd6b9..e1d3638 100644
--- a/arch/arm/cpu/armv7/sunxi/psci.c
+++ b/arch/arm/cpu/armv7/sunxi/psci.c
@@ -153,7 +153,7 @@
 
 	sunxi_power_switch((void *)cpucfg + SUN8I_R40_PWR_CLAMP(cpu),
 			   (void *)cpucfg + SUN8I_R40_PWROFF,
-			   on, 0);
+			   on, cpu);
 }
 #else /* ! CONFIG_MACH_SUN7I && ! CONFIG_MACH_SUN8I_R40 */
 static void __secure sunxi_cpu_set_power(int cpu, bool on)