Fixed wownt32.h to make it usable from inside Wine, and use it to
avoid some duplication of the handle conversion macros.

diff --git a/controls/static.c b/controls/static.c
index 3c07f0b..50042ba 100644
--- a/controls/static.c
+++ b/controls/static.c
@@ -21,6 +21,7 @@
 #include "windef.h"
 #include "wingdi.h"
 #include "wine/winuser16.h"
+#include "wownt32.h"
 #include "cursoricon.h"
 #include "controls.h"
 #include "user.h"