Builds broken

[Nick Alcock]

On 29 May 2019, Christophe Lyon stated:

> Hi Nick,
>
> One of your two recent commits
> Commit f948b2de97884bfb4e5fc11d40a6bea9e0b096ae by nickc
> Sync top level files with versions from gcc.
> Commit e33f2313bf63b77763739732be14b469b4b647b7 by nickc
> Update release tools with libctf support.
>
> broke the builds on many (all?) targets:

Conveniently we have (probably) just obviated the need for these commits
(see commit 9698cf9b1c485edbbeabc9f65bfd0fdef92e3854), so we can
probably fix this by just reverting Nick's commits, if he agrees.
(Or part of them, since the src-release.sh stuff is something I do not
pretend to understand, that might well be worthwhile anyway.)