route_bench: Remove knowledge of libmnl internals, not needed.

Since mnl_socket_get_fd() exists, we can use that.

Thanks to Pablo.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/route_bench.c b/route_bench.c
index 6c6b525..063b15e 100644
--- a/route_bench.c
+++ b/route_bench.c
@@ -24,16 +24,6 @@
 #include <linux/rtnetlink.h>
 #include <linux/filter.h>
 
-/* XXX Ugly knowledge of internals, but there is currently no way
- * XXX provided by the libmnl library to set socket options that are
- * XXX of level other than SOL_NETLINK.   And we need to set one of
- * XXX level SOL_SOCKET to install the socket filter.
- */
-struct mnl_socket {
-	int 			fd;
-	struct sockaddr_nl	addr;
-};
-
 static int usage(void)
 {
 	printf("usage: route_bench [ -o ] [ -l count ]\n");
@@ -178,7 +168,8 @@
 
 	portid = mnl_socket_get_portid(nl);
 
-	err = setsockopt(nl->fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));
+	err = setsockopt(mnl_socket_get_fd(nl), SOL_SOCKET,
+			 SO_ATTACH_FILTER, &filter, sizeof(filter));
 	if (err) {
 		perror("setsockopt");
 		return -1;