Update libpng from 1.6.3 to 1.6.10

Change-Id: I76e81e7fd267d15991cd342c5caeb2fe77964ebf
diff --git a/depcomp b/depcomp
index 3f02f5d..4ebd5b3 100755
--- a/depcomp
+++ b/depcomp
@@ -1,9 +1,9 @@
 #! /bin/sh
 # depcomp - compile a program generating dependencies as side-effects
 
-scriptversion=2012-10-18.11; # UTC
+scriptversion=2013-05-30.07; # UTC
 
-# Copyright (C) 1999-2012 Free Software Foundation, Inc.
+# Copyright (C) 1999-2013 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -552,6 +552,7 @@
   G
   p
 }' >> "$depfile"
+  echo >> "$depfile" # make sure the fragment doesn't end with a backslash
   rm -f "$tmpdepfile"
   ;;