rt_hw_cpu_shutdown: implement default weak function

and remvoe duplicated default functions in each cpu/bsp level

bsp/allwinner_tina/libcpu/cpuport.c

@@ -160,7 +160,7 @@ void rt_hw_cpu_reset()
  *  shutdown CPU
  *
  */
-void rt_hw_cpu_shutdown()
+void rt_hw_cpu_shutdown(void)
 {
     rt_uint32_t level;
     rt_kprintf("shutdown...\n");

bsp/bluetrum/libcpu/cpu/cpuport.c

@@ -52,16 +52,3 @@ rt_uint8_t *rt_hw_stack_init(void       *tentry,
     /* return task's current stack address */
     return (rt_uint8_t *)stk;
 }
-
-/** shutdown CPU */
-void rt_hw_cpu_shutdown(void)
-{
-    rt_uint32_t level;
-    rt_kprintf("shutdown...\n");
-
-    level = rt_hw_interrupt_disable();
-    while (level)
-    {
-        RT_ASSERT(0);
-    }
-}

bsp/imx6sx/cortex-a9/cpu/cpu.c

@@ -17,17 +17,6 @@
  */
 /*@{*/
 
-/** shutdown CPU */
-void rt_hw_cpu_shutdown()
-{
-	rt_uint32_t level;
-	rt_kprintf("shutdown...\n");
 
-	level = rt_hw_interrupt_disable();
-	while (level)
-	{
-		RT_ASSERT(0);
-	}
-}
 
 /*@}*/

bsp/mipssim/drivers/board.c

@@ -26,28 +26,6 @@
 
 extern unsigned char __bss_end;
 
-/**
- * this function will reset CPU
- *
- */
-void rt_hw_cpu_reset(void)
-{
-    rt_kprintf("reboot system...\n");
-    while (1);
-}
-
-/**
- * this function will shutdown CPU
- *
- */
-void rt_hw_cpu_shutdown(void)
-{
-    rt_kprintf("shutdown...\n");
-
-    while (1);
-}
-
-
 /**
  * This is the timer interrupt service routine.
  */

bsp/raspberry-pi/raspi2/cpu/cpu.c

@@ -17,17 +17,6 @@
  */
 /*@{*/
 
-/** shutdown CPU */
-void rt_hw_cpu_shutdown()
-{
-    rt_uint32_t level;
-    rt_kprintf("shutdown...\n");
 
-    level = rt_hw_interrupt_disable();
-    while (level)
-    {
-        RT_ASSERT(0);
-    }
-}
 
 /*@}*/

bsp/raspberry-pi/raspi3-32/cpu/cpu.c

@@ -75,17 +75,5 @@ void rt_hw_spin_unlock(rt_hw_spinlock_t *lock)
  */
 /*@{*/
 
-/** shutdown CPU */
-void rt_hw_cpu_shutdown()
-{
-    rt_uint32_t level;
-    rt_kprintf("shutdown...\n");
-
-    level = rt_hw_interrupt_disable();
-    while (level)
-    {
-        RT_ASSERT(0);
-    }
-}
 
 /*@}*/

bsp/rockchip/rk3568/driver/board.c

@@ -133,7 +133,7 @@ void start_cpu(int argc, char *argv[])
 MSH_CMD_EXPORT(start_cpu, start_cpu);
 
 #ifdef RT_AMP_SLAVE
-void rt_hw_cpu_shutdown()
+void rt_hw_cpu_shutdown(void)
 {
     if (psci_ops.cpu_off)
     {