修复bootstap的bug，并添加renode仿真脚本支持

mkrtos_user/server/hello/src/heap_stack.c

@@ -1,5 +1,5 @@
 
-#define HEAP_SIZE 0
+#define HEAP_SIZE 512
 #define STACK_SIZE 1024
 
 #if defined(__CC_ARM)

mkrtos_user/server/hello/src/main.c

@@ -3,6 +3,18 @@
 
 int main(int argc, char *args[])
 {
+    printf("print test0.\n");
+    printf("print test1.\n");
+    printf("print test2.\n");
+    float a = 1.1;
+    float b = 1.2;
+    float c;
 
+    while (1)
+    {
+        c = a + b;
+        printf("%c %d %f\n", 'a', 1234, 1.1);
+        printf("%c %d %lf\n", 'a', 1234, a * b);
+    }
     return 0;
 }

mkrtos_user/server/init/src/test/printf_test.c

@@ -9,7 +9,7 @@ void printf_test(void)
     float b = 1.2;
     float c;
 
-    while (1)
+    // while (1)
     {
         c = a + b;
         printf("%c %d %f\n", 'a', 1234, 1.1);