Merge branch 'bilelmoussaoui-wip/haecker-felix/update-patch-44023' into 'wip/haecker-felix/update'

enable doc_cfg only for dox feature

See merge request haecker-felix/flatpak-rs!5

flatpak/src/lib.rs

-#![feature(doc_cfg)]
+#![cfg_attr(feature = "dox", feature(doc_cfg))]
 
 extern crate bitflags;
 extern crate gio;