build-sys: build with Vista API by default

Both qemu & qga build with Vista API by default already, by defining
_WIN32_WINNT 0x0600. Set it globally in osdep.h instead.

This replaces WINVER by _WIN32_WINNT in osdep.h. WINVER doesn't seem
to be really useful these days.
(see also https://blogs.msdn.microsoft.com/oldnewthing/20070411-00/?p=27283)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181122110039.15972-4-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

include/qemu/osdep.h

@@ -76,8 +76,8 @@ extern int daemon(int, int);
 
 #ifdef _WIN32
 /* as defined in sdkddkver.h */
-#ifndef WINVER
-#define WINVER 0x0501 /* XP */
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x0600 /* Vista */
 #endif
 /* reduces the number of implicitly included headers */
 #ifndef WIN32_LEAN_AND_MEAN

qga/commands-win32.c

@@ -10,12 +10,8 @@
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  */
-
-#ifndef _WIN32_WINNT
-#   define _WIN32_WINNT 0x0600
-#endif
-
 #include "qemu/osdep.h"
+
 #include <wtypes.h>
 #include <powrprof.h>
 #include <winsock2.h>

util/qemu-thread-win32.c

@@ -11,10 +11,6 @@
  *
  */
 
-#ifndef _WIN32_WINNT
-#define _WIN32_WINNT 0x0600
-#endif
-
 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "qemu/thread.h"