Fix compile failure.

myisam/sort.c

@@ -315,6 +315,7 @@ pthread_handler_decl(thr_find_all_keys,arg)
   uint memavl,old_memavl,keys,sort_length;
   uint idx, maxbuffer;
   uchar **sort_keys=0;
+  DBUG_ENTER("thr_find_all_keys");              /* FIXME why no matching DBUG_RETURN ? */
 
   LINT_INIT(keys);
 
@@ -323,10 +324,7 @@ pthread_handler_decl(thr_find_all_keys,arg)
   if (my_thread_init())
     goto err;
 
-  { /* Expands to declaration, create new block */
-    DBUG_ENTER("thr_find_all_keys"); /* FIXME why no matching DBUG_RETURN ? */
   DBUG_PRINT("enter", ("master: %d", sort_param->master));
-  }
 
   if (sort_param->sort_info->got_error)
     goto err;