[PATCH] build: import gtk-doc support

[Colin Helliwell]

> On 07 September 2017 at 08:32 Aleksander Morgado <aleksander at aleksander.es> wrote:
> 
> > Not sure if this is similar/same, but I have the same sort of issue when enabling introspection (which I now need) and cross-compiling - discussed here back in March.
> > I'm moving over now to using a stable release (i.e. tarball), but it would be useful to have the option to use git checkout.
> 
> You mean you cannot build with introspection enabled from a git checkout?
> 

Ooops, sorry ignore that - I was thinking of NetworkManager!