Mention the GNU origin of some parts from su. Debian patch 438

ChangeLog

@@ -22,6 +22,8 @@
 	Imported from Debian's patch 402-clarify_usermod_usage
 	* man/shadow.5.xml: fix spelling error. Imported from Debian's
 	patch 433_shadow.5-typo_312430
+	* src/su.c: Be up front on the origin of su and mention the GNU
+	origin. Imported from Debian's patch 438_su_GNU_origin
 
 2007-10-27  Nicolas François  <nicolas.francois@centraliens.net>
 

src/su.c

@@ -26,6 +26,24 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+/* Some parts substantially derived from an ancestor of: */
+/* su for GNU.  Run a shell with substitute user and group IDs.
+   Copyright (C) 1992-2003 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
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
 
 #include <config.h>