PATCH: Factor __aeabi_atexit into its own object file

[Paolo Carlini]

Mark Mitchell wrote:

>How about this patch, as a solution?  (To replace the quick hack I
>checked in when you reported this to me.)
>  
>
Ah, if I understand it correctly (i'm not very familiar with 
attribute((nothrow)), just browsed the docs about it), seems a very good 
idea to me. But now I suspect such attribute could be potentially 
usefully added to many more functions? Could you clarify?

Thanks,
Paolo.