selftests/tcp_ao: Zero-init tcp_ao_info_opt

The structure is on the stack and has to be zero-initialized as
the kernel checks for:
>	if (in.reserved != 0 || in.reserved2 != 0)
>		return -EINVAL;

Fixes: b2666053 ("selftests/net: Add test for TCP-AO add setsockopt() command")
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

tools/testing/selftests/net/tcp_ao/setsockopt-closed.c

@@ -21,7 +21,7 @@ static void make_listen(int sk)
 static void test_vefify_ao_info(int sk, struct tcp_ao_info_opt *info,
 				const char *tst)
 {
-	struct tcp_ao_info_opt tmp;
+	struct tcp_ao_info_opt tmp = {};
 	socklen_t len = sizeof(tmp);
 
 	if (getsockopt(sk, IPPROTO_TCP, TCP_AO_INFO, &tmp, &len))