added missing dependency

jni/libpng-1.5.6/autogen.sh

@@ -0,0 +1,34 @@
+#! /bin/sh
+# a quick hack script to generate necessary files from 
+# auto* tools.
+#
+# WARNING: if you run this you will change the versions
+# of the tools which are used and, maybe, required!
+
+# You can define your own replacements in your environment.
+# $AUTOCONF,  $AUTOMAKE, $AUTOHEADER, $AUTOPOINT, $ACLOCAL and $LIBTOOLIZE
+
+touch Makefile.am configure.ac
+{
+   LT=${LIBTOOLIZE-libtoolize}
+   echo "running $LT" >&2
+   $LT --force --copy --automake
+} && {
+   AL=${ACLOCAL-aclocal}
+   echo "running $AL" >&2
+   $AL
+} && {
+   AH=${AUTOHEADER-autoheader}
+   echo "running $AH [ignore the warnings]" >&2
+   $AH
+} && {
+   AM=${AUTOMAKE-automake}
+   echo "running $AM" >&2
+   $AM --force-missing --foreign -a -c
+} && {
+   AC=${AUTOCONF-autoconf}
+   echo "running $AC" >&2
+   $AC
+} &&
+   echo "autogen complete" >&2 ||
+   echo "ERROR: autogen.sh failed, autogen is incomplete" >&2