stdio: Split __get_errname definition from errlist.c

The loader does not need to pull all __get_errlist definitions
and its size is decreased:

Before:
$ size elf/ld.so
   text    data     bss     dec     hex filename
 197774   11024     456  209254   33166 elf/ld.so

After:
$ size elf/ld.so
   text    data     bss     dec     hex filename
 191510    9936     456  201902   314ae elf/ld.so

Checked on x86_64-linux-gnu.

1 files changed, 21 insertions, 0 deletions

diff --git a/sysdeps/mach/hurd/errname.c b/sysdeps/mach/hurd/errname.c
new file mode 100644
index 0000000000..09ddb49478
--- /dev/null
+++ b/sysdeps/mach/hurd/errname.c
@@ -0,0 +1,21 @@
+/* Copyright (C) 1998-2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <mach/error.h>
+
+#define ERR_MAP(value) err_get_code (value)
+#include <stdio-common/errname.c>