Merge GDB 7.5.1

gdb/gnulib/import/ref-del.sin

+# Remove this package from a list of references stored in a text file.
+#
+#   Copyright (C) 2000, 2009-2012 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 3, 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, see <http://www.gnu.org/licenses/>.
+#
+# Written by Bruno Haible <haible@clisp.cons.org>.
+#
+/^# Packages using this file: / {
+  s/# Packages using this file://
+  s/ @PACKAGE@ / /
+  s/^/# Packages using this file:/
+}