ppc64le: gcc 12 vs -mabi=ibmlongdouble

[Florian Weimer]

* Bill Schmidt:

> I ran this by our GCC team, and the tentative consensus is that 
> -mlong-double-64 should override -mabi=ibmlongdouble, rather than 
> reporting an error in the compile flags.  DJ, could you please
> open a bug against the GCC powerpc target?

I went ahead and filed a P1 bug, as agreed on the call:

  -mlong-double-64 should override a previous -mabi=ibmlongdouble
  <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104208>

Thanks,
Florian