mingw: fix error __USE_MINGW_ANSI_STDIO redefined

Always put osdep.h first, and remove redundant stdlib.h include.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201008165953.884599-1-marcandre.lureau@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index 68577ef..47f761e 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -10,8 +10,9 @@
  * See the COPYING file in the top-level directory.
  */
 
-#include <zlib.h>
 #include "qemu/osdep.h"
+
+#include <zlib.h>
 #include "qapi/error.h"
 #include "cpu.h"
 #include "qemu/config-file.h"
diff --git a/tests/test-bitmap.c b/tests/test-bitmap.c
index 2f5b714..8db4f67 100644
--- a/tests/test-bitmap.c
+++ b/tests/test-bitmap.c
@@ -8,7 +8,6 @@
  * Author: Peter Xu <peterx@redhat.com>
  */
 
-#include <stdlib.h>
 #include "qemu/osdep.h"
 #include "qemu/bitmap.h"