[PATCH, libstdc++, testsuite]Skip 62154.cc for target don't support the atomic builtins

[Tony Wang]

It's a very simple patch. Some target don't support atomic builtins, so all 
related test cases should be
disabled. In folder libstdc++-v3/testsuite/18_support/nested_exception, all 
other test cases have already been
disabled for target don't have atomic builtins.

gcc/libstdc++-v3/ChangeLog:
2014-08-21  Tony Wang  <tony.w...@arm.com>

        * testsuite/18_support/nested_exception/62154.cc: Disable
        this test case when target don't have atomic buildins.

diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
b/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
index 9c6725f..da6ed4c 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
@@ -1,4 +1,5 @@
 // { dg-options "-std=gnu++11" }
+// { dg-require-atomic-builtins "" }
 
 // Copyright (C) 2014 Free Software Foundation, Inc.
 //