Merge pull request #1692 from RT-Thread/fix_pthreads

[pthreads] Fix the object check issue.

components/libc/pthreads/pthread_cond.c

@@ -109,6 +109,7 @@ int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr)
 
     /* detach the object from system object container */
     rt_object_detach(&(cond->sem.parent.parent));
+    cond->sem.parent.parent.type = RT_Object_Class_Semaphore;
 
     return 0;
 }

components/libc/pthreads/pthread_mutex.c

@@ -141,6 +141,7 @@ int pthread_mutex_init(pthread_mutex_t *mutex, const pthread_mutexattr_t *attr)
 
     /* detach the object from system object container */
     rt_object_detach(&(mutex->lock.parent.parent));
+    mutex->lock.parent.parent.type = RT_Object_Class_Mutex;
 
     return 0;
 }