Ada support on gcc-6 broken again

[Jan Sommer]

Hello,

building the current tools (gcc-6) from master with Ada support fails.
I will try to post the patch for that to gcc over the weekend (@Joel I 
hope you don't mind me putting you CC for that).
However as gcc-6.1 was just released a month ago, I guess it won't be 
part of an official gcc-release anytime soon.

Could we keep the fix as a patch until the gcc-version of the RSB 
includes it natively?

Best regards,

    Jan