[PATCH] Add missing __throw_exception_again

[Paolo Carlini]

HI,
> This prevents the 22_locale/locale/cons/12352.cc test from crashing.
> Tested on m68k-linux.
Depending on the system, doesn't crash that easily, but indeed the issue 
is real and the patch is right, we want it in 4.7.1 (if not 4.7.0?) and 
mainline.

Thanks,
Paolo.