Update libpng to version 1.6.3

(cherry picked from commit ca2bf81b02c99afa2e76b3b2c6eb232c239221e0)

Change-Id: I313493fa630be9812e503ae24820b2923ed717f3
diff --git a/tests/pngvalid-progressive-standard b/tests/pngvalid-progressive-standard
new file mode 100755
index 0000000..20ecd15
--- /dev/null
+++ b/tests/pngvalid-progressive-standard
@@ -0,0 +1,2 @@
+#!/bin/sh
+exec ./pngvalid --standard --interlace