[Cooker] Another X-Chat dependency

[David Walluck]

It seems that BuildRequires gdk-pixbuf-devel.

Again, for some reason the build does not fail if you build without it but
some features are missing. There's also an --enable-ipv6, which I don't
personally need, but somebody might want that enabled.

-- 
Sincerely,

David Walluck
<[EMAIL PROTECTED]>