[perl-Gtk3] Gtk3::FileChooserDialog: fix typo in usage warning

[Torsten Schönfeld <tsch src gnome org>]

commit 842e294c865d4726185bcc8c8de2bf0d32999e7c
Author: Torsten Schönfeld <kaffeetisch gmx de>
Date:   Tue May 31 20:04:41 2016 +0200

    Gtk3::FileChooserDialog: fix typo in usage warning
    
    https://rt.cpan.org/Public/Bug/Display.html?id=114506

 lib/Gtk3.pm |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/lib/Gtk3.pm b/lib/Gtk3.pm
index 7f06264..c661d8d 100644
--- a/lib/Gtk3.pm
+++ b/lib/Gtk3.pm
@@ -1082,7 +1082,7 @@ sub Gtk3::FileChooserDialog::new {
 
   if (@varargs % 2) {
     croak 'Usage: Gtk3::FileChooserDialog->new' .
-          ' (title, parent, action, backend, button-text =>' .
+          ' (title, parent, action, button-text =>' .
           " response-id, ...)\n";
   }