IAPP: Avoid warnings on unused write

The hlen and len variables are identical here, but only the hlen was
used in the end. Change this to use the len variable to avoid
unnecessary static analyzer warnings about unused writes.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/ap/iapp.c

@@ -361,7 +361,7 @@ static void iapp_receive_udp(int sock, void *eloop_ctx, void *sock_ctx)
 
 	switch (hdr->command) {
 	case IAPP_CMD_ADD_notify:
-		iapp_process_add_notify(iapp, &from, hdr, hlen - sizeof(*hdr));
+		iapp_process_add_notify(iapp, &from, hdr, len - sizeof(*hdr));
 		break;
 	case IAPP_CMD_MOVE_notify:
 		/* TODO: MOVE is using TCP; so move this to TCP handler once it