[gnome-photos] Update to latest libgd

[Debarshi Ray <debarshir src gnome org>]

commit ae2eb7046c02e0098f78278f95bcf208299fb7f0
Author: Debarshi Ray <debarshir gnome org>
Date:   Tue Oct 23 16:02:48 2018 +0200

    Update to latest libgd
    
    Silence some deprecation warnings with GLib 2.57.2 due to
    g_type_class_add_private.

 subprojects/libgd | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/subprojects/libgd b/subprojects/libgd
index 4c928b61..f01717a2 160000
--- a/subprojects/libgd
+++ b/subprojects/libgd
@@ -1 +1 @@
-Subproject commit 4c928b6101c748a96001d673c9e6a7aeb74722e0
+Subproject commit f01717a24fb7f5b24b1f4865818437f060e83932