maint: move the update-copyright rule to gnulib's maint.mk

* gnulib: Update submodule to get latest maint.mk.
* Makefile.am (update-copyright): Remove rule; now it's in maint.mk.
* m4/check-decl.m4: Update sole remaining copyright year list.

Makefile.am

@@ -144,11 +144,3 @@ check-ls-dircolors:
 	  |sed -n '/^  *"/p'|tr , '\n'|sed 's/^  *//'		\
 	  |sed -n 's/^"\(..\)"/\1/p'|sort -u);			\
 	test "$$dc" = "$$ls"
-
-.PHONY: update-copyright
-update-copyright:
-	if test -d .git; then					\
-	  git grep -l -w Copyright				\
-	    | grep -v -E '(^|/)(COPYING|ChangeLog)'		\
-	    | xargs $(srcdir)/build-aux/$@;			\
-	fi

m4/check-decl.m4

@@ -1,8 +1,8 @@
 #serial 24
 # Check declarations for this package.
 
-dnl Copyright (C) 1997-2001, 2003-2006, 2008
-dnl Free Software Foundation, Inc.
+dnl Copyright (C) 1997-2001, 2003-2006, 2008-2009 Free Software
+dnl Foundation, Inc.
 
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,