RFA: Avoid simulator timeouts on more libstdc++ tests

[Paolo Carlini]

Mark Mitchell wrote:
>> Yes, no problem with me. Sorry about the delay answering...
>>     
> Please do not apologize for a response time of a few hours!  You will
> simply make the rest of us feel unreasonably guilty. :-)
>   
Yes, shame on you! :)
> May I also add this patch to the patchset (with obvious ChangeLog entry)
> before checking it in?
>   
Sure, go ahead.

Thanks,
Paolo.