Switch to libtool 2.5.3.

* m4/libtool.m4: Update from libtool-2.5.3, with modifications:
2008-04-06  Bruno Haible  <bruno@clisp.org>
	* m4/libtool.m4 (LT_INIT): When setting LIBTOOL, use
	CONFIG_SHELL; don't assume that the Makefile.in will set SHELL
	to ${CONFIG_SHELL}.
* m4/ltoptions.m4: Likewise.
* m4/ltsugar.m4: Likewise.
* m4/ltversion.m4: Likewise.
* m4/lt~obsolete.m4: Likewise.
* libcharset/m4/*.m4: Likewise.
* build-aux/ltmain.sh: Update from libtool-2.5.3, with modifications:
2017-07-15  Bruno Haible  <bruno@clisp.org>
	Allow building statically linked binaries, through
	LDFLAGS="-static". Apply patch from
	<https://lists.gnu.org/archive/html/bug-libtool/2017-07/msg00000.html>.
	* build-aux/ltmain.sh (func_mode_help, func_mode_link): In the
	link mode, accept option '-static-uninstalled-libs' in place of
	'-static', and make '-static' an equivalent of '-all-static'.
* libcharset/build-aux/ltmain.sh: Likewise.
14 files changed