libselinux: audit2why: remove unused module_state structure

This structure has been empty since its introduction and makes clang
complain when $(filter-out -Werror, $(CFLAGS)) is removed in the
Makefile target for audit2why.lo:

    audit2why.c:443:1: error: empty struct has size 0 in C, size 1 in
    C++ [-Werror,-Wc++-compat]
      struct module_state {
      ^
      1 error generated.

Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>

libselinux/src/audit2why.c

@@ -440,14 +440,11 @@ static PyMethodDef audit2whyMethods[] = {
 
 #if PY_MAJOR_VERSION >= 3
 /* Module-initialization logic specific to Python 3 */
-struct module_state {
-	/* empty for now */
-};
 static struct PyModuleDef moduledef = {
 	PyModuleDef_HEAD_INIT,
 	"audit2why",
 	NULL,
-	sizeof(struct module_state),
+	0,
 	audit2whyMethods,
 	NULL,
 	NULL,