[gnome-font-viewer] build: use an absolute address for libgd submodule

[Cosimo Cecchi <cosimoc src gnome org>]

commit 06d2d9930bf90fabab62c021784c12c7c9bd95a5
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Thu Nov 8 14:05:26 2012 -0500

    build: use an absolute address for libgd submodule
    
    https://bugzilla.gnome.org/show_bug.cgi?id=687718

 .gitmodules |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/.gitmodules b/.gitmodules
index 303eb9b..bfd964e 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,3 @@
 [submodule "libgd"]
 	path = libgd
-	url = ../libgd
+	url = git://git.gnome.org/libgd