add "thread->error = RT_EOK;" in rt_completion_wait

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2107 bbd45198-f89e-11dd-88c7-29a3b14d5316

components/drivers/src/completion.c

@@ -42,6 +42,9 @@ rt_err_t rt_completion_wait(struct rt_completion* completion, rt_int32_t timeout
 		}
 		else
 		{
+			/* reset thread error number */
+			thread->error = RT_EOK;
+			
 			/* suspend thread */
 			rt_thread_suspend(thread);
 			/* add to suspended list */