[binutils-gdb] Fix Cygwin build after 02d04eac

[Jon TURNEY <jturney@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a83c64f567ec7f161b8efb87205d44a2fbbf36f8

commit a83c64f567ec7f161b8efb87205d44a2fbbf36f8
Author: Jon Turney <jon.turney@dronecode.org.uk>
Date:   Wed Nov 2 13:16:16 2022 +0000

    Fix Cygwin build after 02d04eac
    
    Commit 02d04eac "Use strwinerror in gdb/windows-nat.c" also moves
    strwinerror() under the USE_WIN32API conditional, which is not defined
    for Cygwin (and looks like it shouldn't be, as appears to imply
    non-POSIX and MiNGW and WinSock...)
    
    Also enable the declaration and definition of strwinerror() when
    __CYGWIN__ is defined.

Diff:
---
 gdbsupport/errors.cc | 4 ++--
 gdbsupport/errors.h  | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/gdbsupport/errors.cc b/gdbsupport/errors.cc
index 7464df3d067..93fc70ad296 100644
--- a/gdbsupport/errors.cc
+++ b/gdbsupport/errors.cc
@@ -19,7 +19,7 @@
 
 #include "common-defs.h"
 #include "errors.h"
-#ifdef USE_WIN32API
+#if defined (USE_WIN32API) || defined(__CYGWIN__)
 #include <windows.h>
 #endif /* USE_WIN32API */
 
@@ -71,7 +71,7 @@ internal_warning_loc (const char *file, int line, const char *fmt, ...)
   va_end (ap);
 }
 
-#ifdef USE_WIN32API
+#if defined (USE_WIN32API) || defined(__CYGWIN__)
 
 /* See errors.h.  */
 
diff --git a/gdbsupport/errors.h b/gdbsupport/errors.h
index 5a925789893..d67d692e4cb 100644
--- a/gdbsupport/errors.h
+++ b/gdbsupport/errors.h
@@ -99,7 +99,7 @@ extern void malloc_failure (long size) ATTRIBUTE_NORETURN;
 
 extern void flush_streams ();
 
-#ifdef USE_WIN32API
+#if defined(USE_WIN32API) || defined(__CYGWIN__)
 
 /* Map the Windows error number in ERROR to a locale-dependent error
    message string and return a pointer to it.  Typically, the values