Deprecate a.out support for NetBSD targets.

As discussed previously, a.out support is now quite deprecated, and in
some cases removed, in both Binutils itself and NetBSD, so this legacy
default makes little sense. `netbsdelf*` and `netbsdaout*` still work
allowing the user to be explicit about there choice. Additionally, the
configure script warns about the change as Nick Clifton requested.

One possible concern was the status of NetBSD on NS32K, where only a.out
was supported. But per [1] NetBSD has removed support, and if it were to
come back, it would be with ELF. The binutils implementation is
therefore marked obsolete, per the instructions in the last message.

With that patch and this one applied, I have confirmed the following:

--target=i686-unknown-netbsd
--target=i686-unknown-netbsdelf
  builds completely

--target=i686-unknown-netbsdaout
  properly fails because target is deprecated.

--target=vax-unknown-netbsdaout builds completely except for gas, where
the target is deprecated.

[1]: https://mail-index.netbsd.org/tech-toolchain/2021/07/19/msg004025.html
---
 bfd/config.bfd                             | 43 +++++++++++++--------
 bfd/configure.ac                           |  5 +--
 binutils/testsuite/binutils-all/nm.exp     |  2 +-
 binutils/testsuite/lib/binutils-common.exp |  7 +---
 config/picflag.m4                          |  4 +-
 gas/configure.tgt                          |  9 +++--
 gas/testsuite/gas/arm/blx-bl-convert.d     |  2 +-
 gas/testsuite/gas/arm/blx-local-thumb.d    |  2 +-
 gas/testsuite/gas/sh/basic.exp             |  2 +-
 gdb/configure.host                         | 34 +++++++----------
 gdb/configure.tgt                          |  2 +-
 gdb/testsuite/gdb.asm/asm-source.exp       |  6 +--
 intl/configure                             |  2 +-
 ld/configure.tgt                           | 44 +++++++++++-----------
 ld/testsuite/ld-arm/arm-elf.exp            |  4 +-
 ld/testsuite/ld-elf/elf.exp                |  2 +-
 ld/testsuite/ld-elf/shared.exp             |  4 +-
 libiberty/configure                        |  4 +-

1 files changed, 18 insertions, 18 deletions

diff --git a/gprof/po/gprof.pot b/gprof/po/gprof.pot
index 08f7695..890bb92 100644
--- a/gprof/po/gprof.pot
+++ b/gprof/po/gprof.pot
@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: bug-binutils@gnu.org\n"
-"POT-Creation-Date: 2021-01-09 10:56+0000\n"
+"POT-Creation-Date: 2021-08-11 10:49+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -216,7 +216,7 @@ msgstr ""
 msgid "%s: unable to parse mapping file %s.\n"
 msgstr ""
 
-#: corefile.c:89 corefile.c:523
+#: corefile.c:89 corefile.c:524
 #, c-format
 msgid "%s: could not open %s.\n"
 msgstr ""
@@ -246,17 +246,17 @@ msgstr ""
 msgid "%s: -c not supported on architecture %s\n"
 msgstr ""
 
-#: corefile.c:532 corefile.c:637
+#: corefile.c:533 corefile.c:638
 #, c-format
 msgid "%s: file `%s' has no symbols\n"
 msgstr ""
 
-#: corefile.c:537
+#: corefile.c:538
 #, c-format
 msgid "%s: file `%s' has too many symbols\n"
 msgstr ""
 
-#: corefile.c:904
+#: corefile.c:905
 #, c-format
 msgid "%s: somebody miscounted: ltab.len=%d instead of %ld\n"
 msgstr ""
@@ -375,56 +375,56 @@ msgstr ""
 msgid "Report bugs to %s\n"
 msgstr ""
 
-#: gprof.c:254
+#: gprof.c:252
 #, c-format
 msgid "%s: debugging not supported; -d ignored\n"
 msgstr ""
 
-#: gprof.c:340
+#: gprof.c:338
 #, c-format
 msgid "%s: unknown file format %s\n"
 msgstr ""
 
 #. This output is intended to follow the GNU standards document.
-#: gprof.c:428
+#: gprof.c:426
 #, c-format
 msgid "GNU gprof %s\n"
 msgstr ""
 
-#: gprof.c:429
+#: gprof.c:427
 #, c-format
 msgid ""
 "Based on BSD gprof, copyright 1983 Regents of the University of California.\n"
 msgstr ""
 
-#: gprof.c:430
+#: gprof.c:428
 #, c-format
 msgid ""
 "This program is free software.  This program has absolutely no warranty.\n"
 msgstr ""
 
-#: gprof.c:471
+#: gprof.c:469
 #, c-format
 msgid "%s: unknown demangling style `%s'\n"
 msgstr ""
 
-#: gprof.c:494
+#: gprof.c:492
 #, c-format
 msgid ""
 "%s: Only one of --function-ordering and --file-ordering may be specified.\n"
 msgstr ""
 
-#: gprof.c:546
+#: gprof.c:544
 #, c-format
 msgid "%s: sorry, file format `prof' is not yet supported\n"
 msgstr ""
 
-#: gprof.c:600
+#: gprof.c:598
 #, c-format
 msgid "%s: gmon.out file is missing histogram\n"
 msgstr ""
 
-#: gprof.c:607
+#: gprof.c:605
 #, c-format
 msgid "%s: gmon.out file is missing call-graph data\n"
 msgstr ""
@@ -535,17 +535,17 @@ msgstr ""
 msgid "[find_call] 0x%lx: jalr\n"
 msgstr ""
 
-#: source.c:162
+#: source.c:166
 #, c-format
 msgid "%s: could not locate `%s'\n"
 msgstr ""
 
-#: source.c:237
+#: source.c:244
 #, c-format
 msgid "*** File %s:\n"
 msgstr ""
 
-#: utils.c:103
+#: utils.c:105
 #, c-format
 msgid " <cycle %d>"
 msgstr ""