l2tp: remove references to modprobe in documentation

No longer need explicit modprobe's and update to use ip instead
of deprecated ifconfig command.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Documentation/networking/l2tp.txt

@@ -213,15 +213,12 @@ To create an L2TPv3 ethernet pseudowire between local host 192.168.1.1
 and peer 192.168.1.2, using IP addresses 10.5.1.1 and 10.5.1.2 for the
 tunnel endpoints:-
 
-# modprobe l2tp_eth
-# modprobe l2tp_netlink
-
 # ip l2tp add tunnel tunnel_id 1 peer_tunnel_id 1 udp_sport 5000 \
   udp_dport 5000 encap udp local 192.168.1.1 remote 192.168.1.2
 # ip l2tp add session tunnel_id 1 session_id 1 peer_session_id 1
-# ifconfig -a
+# ip -s -d show dev l2tpeth0
 # ip addr add 10.5.1.2/32 peer 10.5.1.1/32 dev l2tpeth0
-# ifconfig l2tpeth0 up
+# ip li set dev l2tpeth0 up
 
 Choose IP addresses to be the address of a local IP interface and that
 of the remote system. The IP addresses of the l2tpeth0 interface can be