Update acrn_vm_ops.c

Author: lyan3

tools/acrn-manager/acrn_vm_ops.c

@@ -47,7 +47,7 @@ static int check_dir(const char *path)
 
 /* List head of all vm */
 static pthread_mutex_t vmmngr_mutex = PTHREAD_MUTEX_INITIALIZER;
-struct vmmngr_list_struct vmmngr_head = LIST_HEAD_INITIALIZER(vmmngr_head);
+struct vmmngr_list_struct vmmngr_head = { NULL };
 static unsigned long update_count = 0;
 
 struct vmmngr_struct *vmmngr_find(const char *name)