Sync with binutils for building binutils with LTO:

50ad1254d50 GCC: Pass --plugin to AR and RANLIB

Detect GCC LTO plugin.  Pass --plugin to AR and RANLIB to support LTO
build.

ChangeLog:

	* Makefile.tpl (AR): Add @AR_PLUGIN_OPTION@
	(RANLIB): Add @RANLIB_PLUGIN_OPTION@.
	* configure.ac: Include config/gcc-plugin.m4.
	AC_SUBST AR_PLUGIN_OPTION and RANLIB_PLUGIN_OPTION.
	* libtool.m4 (_LT_CMD_OLD_ARCHIVE): Pass --plugin to AR and
	RANLIB if possible.
	* Makefile.in: Regenerated.
	* configure: Likewise.

config/ChangeLog:

	* gcc-plugin.m4 (GCC_PLUGIN_OPTION): New.

libiberty/ChangeLog:

	* Makefile.in (AR): Add @AR_PLUGIN_OPTION@
	(RANLIB): Add @RANLIB_PLUGIN_OPTION@.
	(configure_deps): Depend on ../config/gcc-plugin.m4.
	* configure.ac: AC_SUBST AR_PLUGIN_OPTION and
	RANLIB_PLUGIN_OPTION.
	* aclocal.m4: Regenerated.
	* configure: Likewise.

zlib/ChangeLog:

	* configure: Regenerated.

gcc/ChangeLog:

	* configure: Regenerate.

libatomic/ChangeLog:

	* configure: Regenerate.

libbacktrace/ChangeLog:

	* configure: Regenerate.

libcc1/ChangeLog:

	* configure: Regenerate.

libffi/ChangeLog:

	* configure: Regenerate.

libgfortran/ChangeLog:

	* configure: Regenerate.

libgm2/ChangeLog:

	* configure: Regenerate.

libgomp/ChangeLog:

	* configure: Regenerate.

libitm/ChangeLog:

	* configure: Regenerate.

libobjc/ChangeLog:

	* configure: Regenerate.

libphobos/ChangeLog:

	* configure: Regenerate.

libquadmath/ChangeLog:

	* configure: Regenerate.

libsanitizer/ChangeLog:

	* configure: Regenerate.

libssp/ChangeLog:

	* configure: Regenerate.

libstdc++-v3/ChangeLog:

	* configure: Regenerate.

libvtv/ChangeLog:

	* configure: Regenerate.

lto-plugin/ChangeLog:

	* configure: Regenerate.