[kernel] add rt_thread_close()

* [thread] Add rt_thread_close()

This patch introduces a new function `rt_thread_close()` to enhances the
usability and maintainability by providing a dedicated mechanism for
closing threads.

- A new function `rt_thread_close()` is added to the API, providing a
  standardized approach for closing threads.
- The `rt_thread_close()` function removes a thread from the thread
  queue, updates its status to indicate closure, and performs the thread
  timer detaching which is a embedded timer in thread object.
- Additionally, the `rt_thread_detach()` function is modified to utilize
  `rt_thread_close()` internally, streamlining the thread detachment
  process.

Signed-off-by: Shell <smokewood@qq.com>

components/libc/posix/libdl/dlmodule.c

@@ -202,19 +202,11 @@ void dlmodule_destroy_subthread(struct rt_dlmodule *module, rt_thread_t thread)
     /* lock scheduler to prevent scheduling in cleanup function. */
     rt_enter_critical();
 
-    /* remove thread from thread_list (ready or defunct thread list) */
+    rt_thread_close(thread);
+
+    /* remove thread from thread_list (defunct thread list) */
     rt_list_remove(&RT_THREAD_LIST_NODE(thread));
 
-    if ((thread->stat & RT_THREAD_STAT_MASK) != RT_THREAD_CLOSE &&
-        (thread->thread_timer.parent.type == (RT_Object_Class_Static | RT_Object_Class_Timer)))
-    {
-        /* release thread timer */
-        rt_timer_detach(&(thread->thread_timer));
-    }
-
-    /* change stat */
-    thread->stat = RT_THREAD_CLOSE;
-
     /* invoke thread cleanup */
     if (thread->cleanup != RT_NULL)
         thread->cleanup(thread);