Update libpng to 1.2.38 to patch a minor security issue.
diff --git a/scripts/makefile.atari b/scripts/makefile.atari
index 9566d5d..944337d 100644
--- a/scripts/makefile.atari
+++ b/scripts/makefile.atari
@@ -1,8 +1,12 @@
# makefile for libpng
# Copyright (C) 2002 Glenn Randers-Pehrson
# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
-# For conditions of distribution and use, see copyright notice in png.h
-# modified for LC56/ATARI assumes libz.lib is in same dir and uses default
+
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# Modified for LC56/ATARI assumes libz.lib is in same dir and uses default
# rules for library management
#
CFLAGS=-I..\zlib -O