[wing/wip/nacho/poll] Add define

[Ignacio Casal Quinteiro <icq src gnome org>]

commit 66b5f0a45601e0b0204c7496791f7803a7f8bc97
Author: Ignacio Casal Quinteiro <qignacio amazon com>
Date:   Tue Dec 4 11:18:25 2018 +0100

    Add define

 tests/poll.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/tests/poll.c b/tests/poll.c
index bc8d284..44db8e6 100644
--- a/tests/poll.c
+++ b/tests/poll.c
@@ -16,6 +16,8 @@
  * along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
 
+#define _WIN32_WINNT 0x0600
+
 #include <wing/wing.h>
 #include <glib.h>
 #include <Winsock2.h>