Fixed xmlstarlet to find the right libxslt when building on stage 1

textproc/xmlstarlet/xmlstarlet.conf

@@ -0,0 +1,18 @@
+# --- SDE-COPYRIGHT-NOTE-BEGIN ---
+# This copyright note is auto-generated by ./scripts/Create-CopyPatch.
+# 
+# Filename: package/.../xmlstarlet/xmlstarlet.conf
+# Copyright (C) 2007 The OpenSDE Project
+# 
+# More information can be found in the files COPYING and README.
+# 
+# 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
+# the Free Software Foundation; version 2 of the License. A copy of the
+# GNU General Public License can be found in the file COPYING.
+# --- SDE-COPYRIGHT-NOTE-END ---
+
+if ! atstage native; then
+	# help it to find the right libxslt
+	var_append extraconfopt ' ' "--with-libxslt-prefix=$root/$( pkgprefix libxslt )"
+fi