[libffi] Fix libffi.special/unwindtest.cc on Solaris

[Andreas Tobler]

Eric Botcazou wrote:

> Tested on sparc64-sun-solaris2.9, sparc-sun-solaris2.8 and 
> amd64-mandrake-linux-gnu.  OK for mainline?
> 

And on darwin and linuxppc 32 bit.

> 
> 2005-01-11  Eric Botcazou  <ebotcazou@libertysurf.fr>
> 
> 	* testsuite/libffi.special/special.exp (cxx_options): Add -shared-libgcc.

Ok, thanks!

Regards,
Andreas