Fix: custom signal handler not working

kernel/main.c

@@ -42,8 +42,11 @@ void _init(void *dtb)
 
 void main(void *dtb)
 {
+  INFOR("kernel running");
+
   _init(dtb);
 
+  INFOR("Run user process syscall.img");
   run_thread(run_process_by_name, (uint64_t)&"syscall.img");
 
   schedule();