AIX: Add dg-options to tests that override operator new

[Graham Reed]

On 01/24/11 15:45, Paolo Carlini wrote:
> I have no objections, only I would suggest summarizing the issue in a
> small comment preceding the dg-options.

Ah, yes, that would be a good idea.  Something like:

// On AIX, to override libstdc++.a's definition of operator new() and
// delete(), we must both export the symbols from the main program (so
// they are visible at run-time) and activate the run-time (which
// will perform the replacement).

I can re-form the patch if you guys are happy with that phrasing.