lib: Fix a typo in a doc comment
lib: Fix a typo in a doc comment

https://bugzilla.gnome.org/show_bug.cgi?id=697218

Distrotech/geocode-glib,mlundblad/geocode-glib,Distrotech/geocode-glib,mlundblad/geocode-glib,mlundblad/geocode-glib