Fix for "configure invocation" on OpenBSD

[Pavel Roskin]

Hello!

The native shell on OpenBSD removes backslash before double quotes in
here-documents with unquoted delimiters, as opposed to bash and other
shells which preserve the backslash.

Using double backslash everywhere when a single backslash is expected on
output should be safe.

______________________
$ cat <<EOF
> \" \\
> EOF
" \
$ bash
bash-2.04$ cat <<EOF
> \" \\
> EOF
\" \
bash-2.04$
______________________

ChangeLog:

        * acgeneral.m4 (_AC_OUTPUT_CONFIG_STATUS): Use two backslashes
        before double quotes in the copyright notice, since the native
        OpenBSD shell removes single backslashes here-documents with
        unquoted delimiters.

_________________________
--- acgeneral.m4
+++ acgeneral.m4
@@ -3701,7 +3701,7 @@
 m4_ifset([AC_PACKAGE_NAME], [AC_PACKAGE_NAME ])config.status[]dnl
 m4_ifset([AC_PACKAGE_VERSION], [ AC_PACKAGE_VERSION])
 configured by [$]0, generated by GNU Autoconf AC_ACVERSION,
-  with options \"`echo "$ac_configure_args" | sed 's/[[\\""\`\$]]/\\\\&/g'`\"
+  with options \\"`echo "$ac_configure_args" | sed 's/[[\\""\`\$]]/\\\\&/g'`\\"

 Copyright 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001
 Free Software Foundation, Inc.
_________________________

-- 
Regards,
Pavel Roskin