Merge changes from GCC for the config/ directory

Merge changes from GCC for the config/ directory

GCC's config/ChangeLog since the last time this merge was done
(in the binutils-gdb commit 0b4d000cc4e8e77c823) is included at the
end of this commit message.

It is worth noting that the binutils-gdb commit 301a9420d947da1458
added the file config/debuginfod.m4 which is not present in GCC's
config/ directory.  This file is preserved, unmodified, after this
commit.

In order to regenerate all of the configure files, I configured with
--enable-maintainer-mode, and built the 'all' target.  I then did the
same thing on a source tree without this patch, and only committed
those files that changed when this patch was added.

GCC's config/ChangeLog entries:

  2020-02-12  Sandra Loosemore  <sandra@codesourcery.com>

  	PR libstdc++/79193
  	PR libstdc++/88999

  	* no-executables.m4: Use a non-empty program to test for linker
  	support.

  2020-02-01  Andrew Burgess  <andrew.burgess@embecosm.com>

  	* lib-link.m4 (AC_LIB_LINKFLAGS_BODY): Update shell syntax.

  2020-01-27  Andrew Burgess  <andrew.burgess@embecosm.com>

  	* lib-link.m4 (AC_LIB_LINKFLAGS_BODY): Add new
  	--with-libXXX-type=... option.  Use this to guide the selection of
  	either a shared library or a static library.

  2020-01-24  Maciej W. Rozycki  <macro@wdc.com>

  	* toolexeclibdir.m4: New file.

  2019-09-10  Christophe Lyon  <christophe.lyon@st.com>

  	* futex.m4: Handle *-uclinux*.
  	* tls.m4 (GCC_CHECK_TLS): Likewise.

  2019-09-06  Florian Weimer  <fweimer@redhat.com>

  	* futex.m4 (GCC_LINUX_FUTEX): Include <unistd.h> for the syscall
  	function.

  2019-07-08  Richard Sandiford  <richard.sandiford@arm.com>

  	* bootstrap-Og.mk: New file.

  2019-06-25  Kwok Cheung Yeung  <kcy@codesourcery.com>
              Andrew Stubbs  <ams@codesourcery.com>

  	* gthr.m4 (GCC_AC_THREAD_HEADER): Add case for gcn.

  2019-05-30  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

  	* ax_count_cpus.m4: New file.

  2019-05-02  Richard Biener  <rguenther@suse.de>

  	PR bootstrap/85574
  	* bootstrap-lto.mk (extra-compare): Set to gcc/lto1$(exeext).

  2019-04-16  Martin Liska  <mliska@suse.cz>

  	* bootstrap-lto-lean.mk: Filter out -flto in STAGEtrain_CFLAGS.

  2019-04-09  Martin Liska  <mliska@suse.cz>

  	* bootstrap-lto-lean.mk: New file.

  2019-03-02  Johannes Pfau  <johannespfau@gmail.com>

  	* mh-mingw: Also set __USE_MINGW_ACCESS flag for C++ code.

  2018-10-31  Joseph Myers  <joseph@codesourcery.com>

  	PR bootstrap/82856
  	* math.m4, tls.m4: Use AC_LANG_SOURCE.

  	Merge from binutils-gdb:
  	2018-06-19  Simon Marchi  <simon.marchi@ericsson.com>

  	* override.m4 (_GCC_AUTOCONF_VERSION): Bump from 2.64 to 2.69.

config/ChangeLog:

	* ax_count_cpus.m4: New file, backported from GCC.
	* bootstrap-Og.mk: New file, backported from GCC.
	* bootstrap-lto-lean.mk: New file, backported from GCC.
	* bootstrap-lto.mk: Changes backported from GCC.
	* futex.m4: Changes backported from GCC.
	* gthr.m4: Changes backported from GCC.
	* lib-link.m4: Changes backported from GCC.
	* mh-mingw: Changes backported from GCC.
	* no-executables.m4: Changes backported from GCC.
	* tls.m4: Changes backported from GCC.
	* toolexeclibdir.m4: New file, backported from GCC.

binutils/ChangeLog:

	* configure: Regenerate.

gdb/ChangeLog:

	* configure: Regenerate.

gdbserver/ChangeLog:

	* configure: Regenerate.

gdbsupport/ChangeLog:

	* configure: Regenerate.

intl/ChangeLog:

	* configure: Regenerate.

libiberty/ChangeLog:

	* configure: Regenerate.

zlib/ChangeLog.bin-gdb:

	* configure: Regenerate.