[gnome-boxes] Use latest libgd

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 0d77df189ffdd31fba2725e9595ec2221d50c4a4
Author: Zeeshan Ali (Khattak) <zeeshanak gnome org>
Date:   Wed Sep 10 17:55:55 2014 +0100

    Use latest libgd
    
    Don't know of any other advantages but at least it fixes the missing
    checkboxes on selected items in selection mode.

 libgd |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/libgd b/libgd
index ac4ae16..04b2480 160000
--- a/libgd
+++ b/libgd
@@ -1 +1 @@
-Subproject commit ac4ae160ee92fcf7010d0d9420e6f71532627f80
+Subproject commit 04b2480259769709ec34d7ee48294878c94bbbb5