[gnome-photos] Update to latest libgd

[Debarshi Ray <debarshir src gnome org>]

commit a64e059fdee77741eb261d13616c64a10f7a0f64
Author: Debarshi Ray <debarshir gnome org>
Date:   Wed Nov 25 11:08:09 2015 +0100

    Update to latest libgd
    
    Fixes warnings with newer GTK+ and silences some valgrind spew.

 libgd |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/libgd b/libgd
index bf0b5c9..7c12355 160000
--- a/libgd
+++ b/libgd
@@ -1 +1 @@
-Subproject commit bf0b5c96a6b2f4b039fc12c2cef7729fc7cb6ecf
+Subproject commit 7c1235591c4aa866b28c8b8dabdcb3b9084c5763